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 Post subject: Re: Which is bigger, A or B?
Post #21 Posted: Wed Mar 15, 2017 9:08 pm 
Judan

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While we're at it, how strong is Crazy Stone on Android?

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 Post subject: Re: Which is bigger, A or B?
Post #22 Posted: Wed Mar 15, 2017 9:27 pm 
Judan

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Bill Spight wrote:
While we're at it, how strong is Crazy Stone on Android?


Something like KGS 5d, I think. Might depend on your phone's hardware.

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Post #23 Posted: Thu Mar 16, 2017 2:11 am 
Gosei

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I'd just play the hane. It really seems huge.


Oh, I'd play it, too. But this is a discussion, not a bull ring. It seems more interesting to try to tease out whether we have blind spots, to learn how other people (including pros) think, to open up new horizons, to take the scenic route. Even if you end up with the same decision, you might pick up some useful insights for future positions.


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Post #24 Posted: Thu Mar 16, 2017 2:39 am 
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If White plays the hane outside, I could imagine this sequence:

Click Here To Show Diagram Code
[go]$$Wc White plays hane outside
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . O O O 8 . . . . . . . . . . . . |
$$ | . . X O X X 1 . . . . . . . . . . . . |
$$ | . O O X . . 5 . . . . . . . . . . . . |
$$ | O . O X . 6 7 . . . . . . . . . . . . |
$$ | . O X X . 9 . . . . . . . . . . . . . |
$$ | 3 X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | 2 O O O X . . . . . . . . . . . . . . |
$$ | . 4 X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


After White 7, even if Black cuts at 8, I think White can manage the cut-off group pretty well, starting with the hane at 9. The f3 White stone has aji as well.

Wrapping around Black this way has got to be good for White, no?

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 Post subject: Re: Which is bigger, A or B?
Post #25 Posted: Thu Mar 16, 2017 2:52 am 
Oza

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Marcel, better to not play 3. (Wastes ko threat, there is not a black double sente move there, and gives black an opportunity to realise the error of his ways and tenuki. Strangely enough the exchange of 2 for 3 seems to be slightly advantageous for black as it reduces the size of white's follow up there, in sente. Also with your continuation there is a real possibility of white aiming to use the damezumari of the big black wall in his shenanigans with f3, so you don't want to make him gain liberties by taking off the stones).

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 Post subject: Re: Which is bigger, A or B?
Post #26 Posted: Thu Mar 16, 2017 8:40 am 
Judan

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John Fairbairn wrote:
Quote:
I'd just play the hane. It really seems huge.


Oh, I'd play it, too. But this is a discussion, not a bull ring. It seems more interesting to try to tease out whether we have blind spots, to learn how other people (including pros) think, to open up new horizons, to take the scenic route. Even if you end up with the same decision, you might pick up some useful insights for future positions.


Yes, I agree that it's good to consider blind spots and alternative ideas. Personally, this is a challenge for me if I don't have a particular reason to believe a particular idea.

So far, the reasons I've heard to not play the hane is that:
1.) There might be aji on the left.
2.) Pros are more wary of aji than amateurs.

So if we want to really have a discussion, let's dig deeper into this aji.

What aji is concerning on the left? Let's evaluate it.

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 Post subject: Re: Which is bigger, A or B?
Post #27 Posted: Thu Mar 16, 2017 9:30 am 
Oza

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Kirby wrote:
What aji is concerning on the left? Let's evaluate it.


For simplicity's sake let's say the below to 5 happens (as white I would be tempted to play 5 at a like Marcel showed and allow the cut as the hane below 4 is so yummy). Then the obvious first aji is aiming to get the stone at 6 in sente.

Click Here To Show Diagram Code
[go]$$Wc Aji?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 . . . . . . . . . . . . . . . . |
$$ | . . . , . . . 5 . , . . . . . , . . . |
$$ | . . 7 O O O . . . . . . . . . . . . . |
$$ | . . X O X X 1 . . . . . . . . . . . . |
$$ | . O O X . . 3 . . . . . . . . . . . . |
$$ | O . O X . 4 a . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | 2 O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Then the attach and crosscut could be one way to try to settle the position. The problem is black wants sente to come back and net at a but then he can't hang on to the corner.

Click Here To Show Diagram Code
[go]$$Bc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 0 X . . . . . , . . . . . X . . . |
$$ | . . 6 4 7 . . . . . . . . . . . . . . |
$$ | . . O 1 5 . . . . . . . . . . . . . . |
$$ | . 8 3 2 . . . . . . . . . . . . . . . |
$$ | . . 9 . a . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . , . . . O . , . . . . . , . . . |
$$ | . . O O O O . . . . . . . . . . . . . |
$$ | . . X O X X O . . . . . . . . . . . . |
$$ | . O O X . . O . . . . . . . . . . . . |
$$ | O . O X . X . . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | X O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Another problem with the above is the first move wasn't actually sente to kill white on the left, just save the stone, so if the outside 4 stones don't have the g8 cut then white could easily ignore (and 4 might be a tesuji, black saves 5-6 exchange):
Click Here To Show Diagram Code
[go]$$Bc Aji resist
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . 7 . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . 2 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 1 . . . . . . . . . . . . . . . . |
$$ | . . 5 , . . . O . , . . . . . , . . . |
$$ | . 4 3 O O O . . . . . . . . . . . . . |
$$ | . 6 X O X X O . . . . . . . . . . . . |
$$ | . O O X . . O . . . . . . . . . . . . |
$$ | O . O X . X . . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | X O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Not so spectacular for black. Of course this is very direct and likely premature. Better to leave it and hope to make it useful later (e.g. if black answer with one space jump on top left corner and then aims to do something on the side).


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 Post subject: Re: Which is bigger, A or B?
Post #28 Posted: Thu Mar 16, 2017 9:38 am 
Judan

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Uberdude wrote:
Marcel, better to not play 3.


I agree. I did that for the analysis of local tewari, not to say that it should be played right away. Sorry for any confusion. :(

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 Post subject: Re: Which is bigger, A or B?
Post #29 Posted: Thu Mar 16, 2017 9:44 am 
Judan

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As I suggested above, if the aji on the left side is a concern, how about this?

Click Here To Show Diagram Code
[go]$$Wc Aji?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . b . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . 3 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . O O O a . . . . . . . . . . . . |
$$ | . . X O X X 1 . . . . . . . . . . . . |
$$ | . O O X . . . . . . . . . . . . . . . |
$$ | O . O X . . . . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | 2 O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


OC, :w3: leaves the cut at "a", but threatens "b".

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 Post subject: Re: Which is bigger, A or B?
Post #30 Posted: Thu Mar 16, 2017 10:16 am 
Judan

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About this variation:

Click Here To Show Diagram Code
[go]$$Wc Aji?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 . . . . . . . . . . . . . . . . |
$$ | . . . , . . . 5 . , . . . . . , . . . |
$$ | . . 7 O O O . . . . . . . . . . . . . |
$$ | . . X O X X 1 . . . . . . . . . . . . |
$$ | . O O X . . 3 . . . . . . . . . . . . |
$$ | O . O X . 4 a . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | 2 O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


:W7: appears to be the proper way to defend, and feels professional. But it's gore. In a real game, I would probably kick to get sente:

Click Here To Show Diagram Code
[go]$$Wc Aji?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 b c . . . . . . . . . . . . . . |
$$ | . d 7 , . . . 5 . , . . . . . , . . . |
$$ | . . . O O O . . . . . . . . . . . . . |
$$ | . . X O X X 1 . . . . . . . . . . . . |
$$ | . O O X . . 3 . . . . . . . . . . . . |
$$ | O . O X . 4 a . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . X O X . . . . . , . . . . . O . . . |
$$ | . X O X X O . X . . . . . . . . . . . |
$$ | 2 O O O X . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


After black plays 'b' or 'c' or maybe 'd'. I'd have sente to attack the stones.

Admittedly, this feels sloppy.

But why is it bad?

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 Post subject: Re: Which is bigger, A or B?
Post #31 Posted: Thu Mar 16, 2017 11:04 am 
Oza

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Maybe kick isn't bad, it looks a plausible resistance. But it's indulgent reading if you think black would answer. It is a shape played by professionals e.g. http://ps.waltheri.net/database/game/73974/ move 20 or http://ps.waltheri.net/database/game/37399/ move 63.


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Post #32 Posted: Thu Mar 16, 2017 11:33 am 
Gosei

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Pure chance, but I am in the throes of inputting an old game and a position which shows the above dichotomy in terms that are perhaps simpler for kyu players occurred. It also has the merit of a comment by Honinbo Shusai.



White was Okunuki Chisaku, the likely Honinbo heir ahead of Jowa but he died early. He played at 7-dan strength. Black reached 6-dan (he was Suzuki Chisei who formed half of the world's first husband-and-wife pro couple). So, neither side was a slouch.

First, Chisaku had a choice between playing the White triangle stone or at the Black triangle. He chose the centre over both a base and immediate territory.

But these miai points are not miai now (an interesting idea which I've encountered before: moves can be miai at one point and not miai one move later when one has been played), although Chisei clearly thought they were. Shusai said that Black erred as it allowed White to play A. Black should now have played B, C, A.

Although Shusai did not explain why, I'm sure part of the explanation is that (as I said before) a Tennozan move is rarely bad, i.e. a stake in the centre is very important. So, here, Black has surrendered his stake in the centre, but interestingly White got absolutely no territory in this quadrant (in fact he lost 8 stones on the upper side). He got a measly few points on the right edge but the main effect was that he connected up with his peculiar carpenter's square in the lower right. This combination meant he deprived Black of any territory on the right side and snatched the tasty corner morsel from Black's lips. Although Black got the 8-stone group he struggled to make territory anywhere else, and the apparent thickness on the lower right side netted a mere ten points while White got the whole of the lower side and forced an early resignation.

I think this centre versus corners/sides issue can be visualised as a series of nested boxes, each containing a mystic message and to be opened in turn as you become stronger. The outside box tells us that the dan player realises the centre is important. The next message tells the high-dan player that the centre is even more important then the dan player thinks. The next box tells us that a pro realises the centre is even more important then the high-dan amateur thinks. The next tells us that a top pro realises the centre is even more important than the low pro thinks. The last box tells us that AlphaGo and Go Seigen both know the centre is even more important than the top pros think.


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 Post subject: Re: Which is bigger, A or B?
Post #33 Posted: Thu Mar 16, 2017 12:12 pm 
Judan

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Uberdude wrote:
Maybe kick isn't bad, it looks a plausible resistance. But it's indulgent reading if you think black would answer. It is a shape played by professionals e.g. http://ps.waltheri.net/database/game/73974/ move 20 or http://ps.waltheri.net/database/game/37399/ move 63.


Thanks for these examples. I actually expected a reason why the kick was bad, though I am inclined to play it.

I am ofren reluctant to play gote, but sometimes playing gote feels thick and strong (eg. after playing gote and getting a thick shape, there may be a stronger local follow up).

Since you had a different first instinct than me, I was a little curious.

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Post #34 Posted: Thu Mar 16, 2017 1:32 pm 
Oza

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Kirby wrote:
Uberdude wrote:
Maybe kick isn't bad, it looks a plausible resistance. But it's indulgent reading if you think black would answer. It is a shape played by professionals e.g. http://ps.waltheri.net/database/game/73974/ move 20 or http://ps.waltheri.net/database/game/37399/ move 63.


Thanks for these examples. I actually expected a reason why the kick was bad, though I am inclined to play it.

I am ofren reluctant to play gote, but sometimes playing gote feels thick and strong (eg. after playing gote and getting a thick shape, there may be a stronger local follow up).

Since you had a different first instinct than me, I was a little curious.


A few years ago at the US go congress, a friend and I were talking to Maeda sensei, and he told us that, apart from the endgame, sente is bad. Now, granted he was addressing this to a 5d player so it shouldn't be taken entirely literally, but his reasoning was basically that sente gains nothing since it's your privilege anyways, and that gote moves are the ones that confer real gains.


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Post #35 Posted: Thu Mar 16, 2017 4:48 pm 
Judan

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skydyr wrote:
A few years ago at the US go congress, a friend and I were talking to Maeda sensei, and he told us that, apart from the endgame, sente is bad. Now, granted he was addressing this to a 5d player so it shouldn't be taken entirely literally, but his reasoning was basically that sente gains nothing since it's your privilege anyways, and that gote moves are the ones that confer real gains.


Well, that is true in the endgame, as well. So perhaps there is more to Maeda's thinking than got across.

OC, the best thing is to make gote plays with sente. ;) That happens a lot at the kyu level.

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Post #36 Posted: Fri Mar 17, 2017 12:27 am 
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BlindGroup wrote:
EDIT: Drew, apologies if this seems obvious. I was mislead by your "infant" rank ;-). Looking at your other posts, I'm guessing my comments are not useful. However, I'm leaving them up in the hopes that they might be useful for newer players.

No apology necessary. You did an excellent job articulating my thoughts when I could not and I appreciate that!

My sincere thanks to everyone who has so enthusiastically participated in this thread. I hemmed and hawed over posting this question because it seemed so basic, but while I was able to see - once prompted - that there was something at B after mechanically playing A during the game, I was unable to conceptualize a useful implementation, so post it I did.

Thankfully my little question attracted just about every 19x19 luminary around for an energetic chat! :bow:


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Post #37 Posted: Fri Mar 17, 2017 4:27 am 
Gosei

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Quote:
A few years ago at the US go congress, a friend and I were talking to Maeda sensei, and he told us that, apart from the endgame, sente is bad. Now, granted he was addressing this to a 5d player so it shouldn't be taken entirely literally, but his reasoning was basically that sente gains nothing since it's your privilege anyways, and that gote moves are the ones that confer real gains.


Yes. And one of the real gains of gote moves (by which we should really understand honte moves and the like) is that they leave behind sente moves - usually more than one. This is the basis of the classic book on "Gote no sente" by Sekiyama Riichi. This in turn is based on kendo, and it is worth viewing through that prism. If we try to visualise ourselves in a sword fight where the opponent comes rushing at us, I suspect most of us are likely to imagine ourselves deftly retreating (gote) rather than rushing back at him or running away (tenuki). That's because we like to see ourselves as not just brave but clever, so we would take time to think and imagine ourselves doing the serenely clever stuff. Our minds are more important than our swords.

But stones in go are not as sharp as swords and that dulls our responses. In go, amateurs tend to think the clever stuff is to resist the opponent's sente with kiai or to tenuki. That's often just grandstanding. Strong players will rather just accept gote and wait for the chance to strike back later on.

That's fine as far as it goes, but a truly strong player also has the ability to assume a gote position even when not faced with an immediate threat. In simplest terms in go this translates into making bases and honte.

Another point to mull over is that kiai is badly translated as "fighting spirit." This tends to conjure up Rambo-esque behaviour in western amateurs. The term just means matching your ki (qi) with your opponent's. That can cover fighting back immediately, of course, but it can also mean taking up a gote position so that your yin matches his yang. But in either case the point to be alert to is that this is not a static match. You are supposed to be trying to have the momentum move in your favour. That may mean tempting the sente opponent to overreach (in go that may include getting him to lose his future options or fill in liberties by playing his sentes too early). It may instead mean coiling up like a spring in a gote position. In go, as Sekiyama teaches, the important thing to take away about gote is to play it so that it likewise represents a coiled spring. If you play a gote that has no spring in it, you have possibly made an inefficient move somewhere along the line, and it is always worth tracing back to see where. It's surprisingly common to see that the inefficient backtracked move turns out to have been a sente when a gote would have been better.

(To forestall the usual questions, I don't think Sekiyama's book is in print. I think my copy is from the 1940s.)


This post by John Fairbairn was liked by: joellercoaster
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 Post subject: Re: Which is bigger, A or B?
Post #38 Posted: Fri Mar 17, 2017 6:56 am 
Dies with sente

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Kirby wrote:

It is a good point that professionals, compared to amateurs, may very well be better at exploiting aji, and also in showing that positions that are seen to be thick are not actually thick.

For this reason, yes, we must question our judgment as amateurs when we think something is thick. We should question our judgment when we think that there is little aji to exploit in a position. After all, we could be wrong- we are only amateurs.

That being said, this does not mean that our judgment is always wrong. Just because pros are good at exploiting aji, it does not mean that we always underestimate the aji that's present.

We cannot base decisions off of this.

...


I like this. We shouldn't disregard our own judgements when seeing stronger players' ideas.

The subject problem is a nice one. I've thought about it for several minutes, flickering from one side to the other. It seems very difficult to choose - taking A leaves extra aji in black's position with the dead W stone, and both A and B help with the aji with the dead black stone.

I've settled towards taking A myself - when black plays in the centre, i think there is a good chance W will get sente for the good point at the bottom (enclose corner + reduce the area) or some other big place (top left). A=20 points + life and death just feels too big. However note that taking A leaves black a nice ko threat.

___

@uberdude I don't see any reason not to kick compared to capturing directly in this position. As you say, B will not respond, but shorting the liberties is important, especially if you aim to crosscut. And yes, tenuki originally seems reasonable.

And your attach crosscut for B looks like a good idea, possibly overplay against the W wall, but at the point where you are worried for B, actually B should double hane, and I think B is fine.

@John Fairbain In your Chisaku example, I think it is more that the 3-3 in this position is just locally not such a powerful move, as B already has P17 and W already has R15. So if W took it , B could just hane and W would have to retreat again. Also, the N17 invasion remains, hurting both B groups, and N16 may well be bigger than R17. The value of R17 here is primarily in attacking W, not points, so if W is safe in the centre, especially with the N17 weakness, W isn't unhappy. (of course W isn't all that safe, so B's play is understandable) It is possible that B was worried W might get sente to invade around M16, but that would just be a fight, and P12 is the biggest point, so I think I agree with Shusai here.

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 Post subject: Re: Which is bigger, A or B?
Post #39 Posted: Fri Mar 17, 2017 6:44 pm 
Lives in sente

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I had an experience like this in a tournament game last year.

Click Here To Show Diagram Code
[go]$$
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O O 1 . . . . . . . . . . . X X O . |
$$ | a X O X . X . . . . . . . . X . X O . |
$$ | . O X , . . . . . , . X . . . X O . . |
$$ | . O X . . . . . . . . . . . . X O O . |
$$ | . X X X . . . . . . . . . O X O X X . |
$$ | . . O X . . . . . . . . . . O O O . . |
$$ | . . O O X . . . . . . . . . . . . . . |
$$ | . . O X b . . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . X . X . X . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . O . O . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

I was White, and Black just played :b1:, which we both assumed was sente, because of the threat of a. But Crazy Stone strongly prefers for White to give the group up and tenuki (e.g., at b), because Black has not only spent two moves to kill the upper left group, they're two moves that in retrospect are deep inside his own territory. My opponent and I were both very surprised afterwards to hear its opinion.

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 Post subject: Re: Which is bigger, A or B?
Post #40 Posted: Fri Mar 17, 2017 11:02 pm 
Oza

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dfan, how did you live? I hope it wasn't talking the stone but hane on 1st line under :b1: as that's at least sente to sneak in the top side a bit next (which might not be sente on this board now but at least you have a follow up).

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