97: topazg vs Mark356 Semi-open

topazg · Post by **topazg** » Thu Feb 10, 2011 4:46 am

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , 6 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Mark356 · Post by **Mark356** » Thu Feb 10, 2011 5:34 am

First thoughts:

Interesting reply. I was sure that he'd play k3 very soon, because it makes e3 look kind of ridiculous. However, this reply is both a little more stable (it's smaller) and a little more aggressive (aims to mitigate the influence of my shimari). I'm not quite sure what to do now.

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . h . . . . . d c . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . i . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . a . . | $$ | . . . . . . . . . . . . . . . . b . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . e , . . . . . , . . . . . , 6 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . f , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . g . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

I could just reply locally, and make a two or three space jump, at A or B. A has the advantage of settling right away, and starting to realize the potential of the shimari, B wants to pick a fight. If I want to settle that group now, I would probably do so at A. But I don't have to settle it now, because if he plays A, I can just swing the other way, to C or D, and if he plays the approach at C, I still have the option of settling at A. But if I settle now, I would be able to attack a play at C immediately rather than getting dressed first.

E is the next point I'm considering. I really think it was premature to play e3 rather than d4. However, this sort of shimari is possible. The usual attack is the C4 keima at F. I don't want to play at F myself, or definitely not too soon, because then he'll just play at E. But if I play E and he plays F, I then play a 3-point extension/1 point pincer, and settle both my groups while his is running.

Given that G is still open, I may as well play it. But the problem is that not only does the joseki normally end in gote, White's last move is to extend to White 6. Therefore, if I were to start playing this joseki now, White would either finish by attacking my unsettled group at its base, or just by taking sente somewhere else.

That leaves the normal approaches at H and I. If there were some way I could end those approaches in sente, then I definitely want to play them. I'm thinking maybe I could play H, expecting a pincer, then play E. White will probably then attack the H stone, and I will live under, and at the end finish by making a two-point jump from E. The problem with this plan is that first, White could play a positive response rather than a pincer-- in fact, white could easily respond to H at E-- and second, White can force me to live in gote.

topazg · Post by **topazg** » Thu Feb 10, 2011 5:50 am

Spoiler (Until move 30 or so)

The reason I didn't like K3 was that it doesn't really interest my lower right stone enough. Naturally it's a point useful to Black, but this is fine:

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . 8 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . 7 , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . 6 . . . . . 9 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

I was less keen on White's ability to make his stones in the lower right work now. I have the ladder towards the top left, so I can force you into the corner, but that means you have 3 good corner positions, and White's compensation isn't that clear to me.

When I took the 5-4 in the lower right, I deliberately aimed at making the right side really interesting to both of us - making a sort of miai of the right and the remaining empty corner. Had I picked, for example, a 3-4 at Q3, I would feel less confident finding an easy way of addressing an approach on that side, as Black can easily make a strong framework. The 4-4 is probably ok too, but will lead to yet another bunch of variations as you can still approach at R6 usefully. By choosing the 5-4, I intended on making the approach to my corner from the right side hard to play.

Laman · Post by **Laman** » Thu Feb 10, 2011 6:47 am

hmm, i am not really sure how should i comment on an open malkovich, but if i keep it same as every malkovich, here are my thoughts about Mark's thoughts

Click Here To Show Diagram Code: [go]$$Bcm1 Diagram 1 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . a . . | $$ | . . . . . . . . . . . . . . . . b . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . e , . . . . . , . . . . . , 6 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . f , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

in the upper right corner, i would strongly prefer black 'b' to black 'a'. 'a' seems to unambitious to me and 'b' creates no real weakness

but both 'a' and 'b' are in the wrong direction - right side was indeed big, but that was before w6, now it became pretty small. if i wanted to develop the shimari, it would be by b K17 extension

e might be little problematic, though i understand your intention to use it as a pre-pincer. it just looks like an awkward extension (developing a side where you haven't settled the corner yet) and i can't get rid of a feeling that white would be still happy to take 'f'

i would probably think about playing f or not so usual loose shimari b D15.

Click Here To Show Diagram Code: [go]$$Bcm7 Diagram 2, possible continuation $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 7 . . . . . . . . . . . . . . . | $$ | . . 8 . . 5 . . 9 . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 6 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . b . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 2 , . . . . . , . . . . . , O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . a . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . B , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . 3 . . . . 4 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

i believe this is possible continuation and the position is still pretty even. black lower side is low and he has a gap at the upper side, but he gets play either 'a' or 'b' and white is also not rock-solid

however, shimari b D15 also interests me. it emphasize the lower side and white faces a decision - if he makes a shimari with w Q3 komoku, black happily extends along the lower side. if white takes K3 or a near point, black invades white's corner (similar to w 'f' after black 'e')

i can't say for sure i am right, just some thoughts

Mark356 · Post by **Mark356** » Fri Feb 11, 2011 12:38 am

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , 6 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . 7 , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

I think Laman is right. Enclosing this corner is big. It settles my stone. More importantly, it is sente: I expect White to play near c10 very soon. (Furthermore, I expect to be forced to play at k3 soon.) Next, I will approach the top: if White pincers, I will counter-pincer, and although my group will be small, it will live in the middle of White's formation. If White defends, I'll get a nice piece of the top.

Knowing that this is my plan, an interesting move for White might be to simply make a shimari, perhaps a large knight's move. I can't approach a large knight's move the same way I can approach a hoshi, and invading under it only gets about six points and gives White terrific influence. It would also mean that I can't extend so far from my shimari up top. However, if White plays a small two-point extension from the hoshi, I get to play the big midpoint.

The other move that made it to the finals was to approach the top stone first. However, it is not sente for two reasons: first, a hoshi can always live; secondly, if I approached, it would be bigger for White to either settle the 4-5 stone or attack my 5-3, either of which are sente. Finally, if I were to approach the hoshi now, either I would have to play the line to the end regardless of sente, or I would tenuki (perhaps to play this move) and accept that I'm throwing away a few stones. So why not just play here to start with? With this move, White does still have sente moves against my groups-- the top group isn't even settled-- but it's harder.

It's kind of silly to start with two shimari like this, especially when White is trying to be so fast and influential. If I didn't want to take care of my stone immediately, I should have played a hoshi. In fact, part of my reasons for playing this rather than the hoshi were because of what I would do if White tried to attack it. In a way, this move destroys the directionality of the 5-3. However:

Yilun Yang writes that playing a follow-up to a 5-3 is bigger than approaching a hoshi;
Lee Changho once played almost the same sequence, playing a shimari to force the opponent to play the big point, then approaching the hoshi;
Shusaku would rather ignore an approach to another stone and claw his way out of a nasty pincer than leave a stone unsettled;
Having healthy stones is very important.

So I think Laman is right. But next time, I think it'll be easier to decide if I wait until after I make my move to read the comments!

EdLee · Post by **EdLee** » Fri Feb 11, 2011 1:36 am

topazg · Post by **topazg** » Fri Feb 11, 2011 4:03 am

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . 8 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

What an interesting opening already. I've opted for my normal way of approaching the shimari extension obstruction (or whatever you'd call it). Local expectations are as follows:

Click Here To Show Diagram Code: [go]$$Bcm9 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . W . 2 . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Bcm9 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . 4 . . . , . . . . X , X . . | $$ | . . 2 . . . . . . . . . . . . . . . . | $$ | . . 1 3 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 5 . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . W . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 6 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Bcm9 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . 1 . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . W . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

So, why this side? Well, firstly, both corners are interested in the left hand side. Actually, my "interest" calculations give Black's interest a bit higher than White's (I consider a shimari's secondary extension to be half an interest, and a full interest if already extended the other side, and a 4-4 as having a full interest. A shimari's primary direction I consider 1.5 interests

), so the urgency of a play on the left seems pretty high. The top is also interesting, though slightly less so because Black's shimari is not targeting it quite as strongly as the right. However, as it's a high stone at P16, it's fairly important to get to the top first.

The bottom edge is relatively uninteresting to both sides right now. If White completes his shimari in the lower right it becomes relatively important, and I genuinely considered this move, as miai of the edges is fine for me, especially when I get a sort of double wing formation from doing so which would be nice. However, it increases the interest in the bottom enough that Black might play at the bottom first, and then we end up with this position on the left anyway. Not only that, but even a short approach from this shimari increases in value of Black has a stone on the bottom edge. As a result, and as Black still has to decide on how to handle the lower right, I'm going to leave it for now, and consider my options of what I do with that 4-5 dependent on Black's approach. Because Black has a low shimari in the bottom left with respect to the bottom edge, the urgency of that area feels lower right now.

EdLee · Post by **EdLee** » Fri Feb 11, 2011 4:34 am

Spoiler.

Mark356 · Post by **Mark356** » Fri Feb 11, 2011 6:45 am

Trigger

Click Here To Show Diagram Code: [go]$$Bcm9 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . 4 . . . , . . . . X , X . . | $$ | . . 2 . . . . . . . . . . . . . . . . | $$ | . . 1 3 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 5 . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . W 7 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 6 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Aphelion · Post by **Aphelion** » Fri Feb 11, 2011 7:22 am

To Mark:

Not for Mark:

Click Here To Show Diagram Code: [go]$$Bcm9 An alternative $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . 9 3 5 . 7 . . . . . . . . . . . . . | $$ | . 7 4 O 6 . . . . , . . . . X , X . . | $$ | . 8 0 . . . . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 2 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . W . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

White could also play like above and the marked move becomes ideally positioned, with white taking sente. I'm not sure that this is best, but this simply demonstrates that Black's move in no way "punishes" White, at least locally.

topazg · Post by **topazg** » Fri Feb 11, 2011 7:39 am

Click Here To Show Diagram Code: [go]$$Bcm11 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . 6 , . . . . . , . . . . . , O . . | $$ | . . O 5 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Spoiler:

Normally, playing into the hane around the head of two stones is a bad thing shape-wise, although there are common josekis that do it explicitly (for example, involving contacting the high approach to a 3-4 stone). So, why here? Well, I've just taken the key shape point locally. If I hane:

Click Here To Show Diagram Code: [go]$$Bcm11 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . 7 a . . . . . , . . . . . , O . . | $$ | . . O 5 . . . . . . . . . . . . . . . | $$ | . . . 6 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

The cut at "a" is very hard to make work, and White simply must defend his position, allowing Black to force White on the outside and keep sente. White's eyespace here is very low, and is still not settled, so the potential for long term discomfort is high. If I extend (normally a good way of keeping sente), this shape point is still upsettingly good for Black, fixing his group and leaving White without two clear eyes. I could continue my hane as follows:

Click Here To Show Diagram Code: [go]$$Bcm11 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . 7 9 . . . . . , . . . . . , O . . | $$ | . . O 5 8 . . . . . . . . . . . . . . | $$ | . . a 6 b . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

But here, neither "a" nor "b" are satisfying. The outside influence from "b" doesn't seem to have anywhere to go, and the loss of allowing Black that cut is quite large. Likewise, White connecting at "a" is overconcentrated and I'm not convinced two eyes are formed, let alone the annoyance of Black being able to cut strongly at "b" himself.

So, instead, I opt for a sequence that settles my group completely and undermines his base:

Click Here To Show Diagram Code: [go]$$Bcm11 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . b 9 . . . . . . . . . . . . . . . . | $$ | . 8 X . . . . . . . . . . . . . . . . | $$ | . . 6 7 . . . . . , . . . . . , O . . | $$ | . . O 5 . . . . . . . . . . . . . . . | $$ | . . 0 . . . . . . . . . . . . . . . . | $$ | . . . . . a . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Now it is relatively hard for Black to seal that group in, and impossible to do so in sente. "a" will be a big move potentially depending on what happens on the bottom edge, and "b" isn't tiny either as it is sente for Black due to my group stability. That's not to say I'd respond locally. If Black plays immediately at "b", I'd respond with "a", but it is still something that has reasonable enough value. The problem is, I need to avoid reductions like this:

Click Here To Show Diagram Code: [go]$$Wcm50 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | 9 . . . . . . . . . . . . . . . . . . | $$ | 8 7 . . . . . . . . . . . . . . . . . | $$ | 6 5 . O . O . . . , . . . . X , X . . | $$ | 0 4 O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . 2 . . . . . . . . . . . . . . . . . | $$ | . 1 X . . . . . . . . . . . . . . . . | $$ | . O X . . . . . . . . . . . . . . . . | $$ | . . O X . . . . . , . . . . . , O . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

As a result, I'm reluctant to play "b" at all if I can avoid it, which in turn makes playing "a" earlier on that little bit larger.

EdLee · Post by **EdLee** » Fri Feb 11, 2011 8:03 am

Click Here To Show Diagram Code: [go]$$Wm14 $$ --------------- $$ | . . . . . . . $$ | . . . . . . . $$ | . . . . . . . $$ | . . . O . O . $$ | . . O . . . . $$ | . . X X . . . $$ | . . . . . . . $$ | . . . . . . . $$ | . . X . . . . $$ | . . . , . . . $$ | . . O . . . . $$ | . . . . . . . $$ | . . . . . . . $$ | . . 1 . . . . $$ | . . . . . . . $$ | . . X , . . . $$ | . . . . X . . $$ | . . . . . . . $$ | . . . . . . . $$ ---------------[/go]

For reference...

EdLee · Post by **EdLee** » Fri Feb 11, 2011 8:22 am

Spoiler. EDIT: Unhidden after :w20:

.

topazg wrote:I opt for a sequence that settles my group completely and undermines his base:
$$Bm11
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . . . , . . . . X , X . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 9 . . . . . . . . . . . . . . . . |
$$ | . 8 X . . . . . . . . . . . . . . . . |
$$ | . . 6 7 . . . . . , . . . . . , O . . |
$$ | . . O 5 . . . . . . . . . . . . . . . |
$$ | . . 0 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . X , . . . . . , . . . . . , . . . |
$$ | . . . . X . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code
[go]$$Bm11 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 9 . . . . . . . . . . . . . . . . | $$ | . 8 X . . . . . . . . . . . . . . . . | $$ | . . 6 7 . . . . . , . . . . . , O . . | $$ | . . O 5 . . . . . . . . . . . . . . . | $$ | . . 0 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

This may not go according to W's plan:

Click Here To Show Diagram Code: [go]$$Wm1 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . O . . . , . . . . X , X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . 1 X . . . . . . . . . . . . . . . . | $$ | . 5 O X . . . . . , . . . . . , O . . | $$ | 7 4 O X . . . . . . . . . . . . . . . | $$ | . 3 2 . . . . . . . . . . . . . . . . | $$ | . 6 8 . . . . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

This seems a big loss both locally and globally for W.
Also, :b15:

attach does not appear in any pro games (local left-side search in SmartGo).

Magicwand · Post by **Magicwand** » Fri Feb 11, 2011 8:31 am

EdLee wrote:Spoiler
This seems a big loss both locally and globally for W.
Also, attach does not appear in any pro games (local left-side search in SmartGo).

Bill Spight · Post by **Bill Spight** » Fri Feb 11, 2011 8:52 am

Spoiler:

Click Here To Show Diagram Code: [go]$$Bcm1 Prisoner Count: B-0 W-0 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . X , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , W . . | $$ | . . 8 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . X , . . . . . , . . . . . , . . . | $$ | . . . . X . . . . . . . . . . . 9 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

is standard when White has made the extension.

Life In 19x19

97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re: 97: topazg vs Mark356 Semi-open

Re:

Re: 97: topazg vs Mark356 Semi-open