115 - robinz v. 1986

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EdLee
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Post by EdLee »

Click Here To Show Diagram Code
[go]$$B
$$------------------+
$$. O . . . . . . . |
$$. O X X X . . . . |
$$X X O O O O O O . |
$$X O O X X X X O . |
$$O X X O . . X X X |
$$. . O . O X W W 3 |
$$. . . . . X X X W |
$$. . . . X . X O X |
$$. . . X . X O O 5 |
$$O . X . X X X O 7 |
$$. . X O O O X O 9 |
$$. O O X X O O O . |
$$. . . O X O X O O |
$$. . . O X X X X O |
$$. . O . O X . X O |
$$. . . O 4 X . X X |
$$O . . O . O X 1 0 |
$$. . . . . O X O B |
$$. . . . . 6 O 2 8 |
$$------------------+[/go]
Click Here To Show Diagram Code
[go]$$Bm11
$$------------------+
$$. O . . . . . . . |
$$. O X X X . . . . |
$$X X O O O O O O . |
$$X O O X X X X O . |
$$O X X O . . X X X |
$$. . O . O X . . X |
$$. . . . . X X X . |
$$. . . . X . X O X |
$$. . . X . X O O X |
$$O . X 1 X X X O X |
$$. . X O O O X O X |
$$. O O X X O O O . |
$$. . . O X O X O O |
$$. . . O X X X X O |
$$. . O . O X . X O |
$$. . . O O X . X X |
$$O . . O . O X X O |
$$. . . . . O X O . |
$$. . . . . O O O O |
$$------------------+[/go]
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Re:

Post by ez4u »

Obs:

EdLee wrote:
Click Here To Show Diagram Code
[go]$$B
$$------------------+
$$. O . . . . . . . |
$$. O X X X . . . . |
$$X X O O O O O O . |
$$X O O X X X X O . |
$$O X X O . . X X X |
$$. . O . O X W W 3 |
$$. . . . . X X X W |
$$. . . . X . X O X |
$$. . . X . X O O 5 |
$$O . X . X X X O 7 |
$$. . X O O O X O 9 |
$$. O O X X O O O . |
$$. . . O X O X O O |
$$. . . O X X X X O |
$$. . O . O X . X O |
$$. . . O 4 X . X X |
$$O . . O . O X 1 0 |
$$. . . . . O X O B |
$$. . . . . 6 O 2 8 |
$$------------------+[/go]
Click Here To Show Diagram Code
[go]$$Bm11
$$------------------+
$$. O . . . . . . . |
$$. O X X X . . . . |
$$X X O O O O O O . |
$$X O O X X X X O . |
$$O X X O . . X X X |
$$. . O . O X . . X |
$$. . . . . X X X . |
$$. . . . X . X O X |
$$. . . X . X O O X |
$$O . X 1 X X X O X |
$$. . X O O O X O X |
$$. O O X X O O O . |
$$. . . O X O X O O |
$$. . . O X X X X O |
$$. . O . O X . X O |
$$. . . O O X . X X |
$$O . . O . O X X O |
$$. . . . . O X O . |
$$. . . . . O O O O |
$$------------------+[/go]


White should not play 2 above immediately.
Click Here To Show Diagram Code
[go]$$B
$$------------------+
$$. O . . . . . . . |
$$. O X X X c . . . |
$$X X O O O O O O . |
$$X O O X X X X O . |
$$O X X O . . X X X |
$$. . O . O X O O 7 |
$$. . . . . X X X O |
$$. . . . X . X O B |
$$. . . X . X O O 2 |
$$O . X 5 X X X O a |
$$. . X O O O X O 3 |
$$. O O X X O O O 9 |
$$. . . O X O X O O |
$$. . . O X X X X O |
$$. . O . O X . X O |
$$. . . O 8 X b X X |
$$O . . O . O X 1 . |
$$. . . . . O X O X |
$$. . . . . 6 O 4 0 |
$$------------------+[/go]

Black takes the ko at the marked point next. Black is ahead (White has to ignore one threat to play at "b" and then a second to take the bottom ko), but this is a flower-viewing ko for White. White has an internal threat at "a", followed by various ko threats at the top ("c", etc.).
Dave Sigaty
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- Marcus Aurelius; Meditations, VIII 21
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Re: 115 - robinz v. 1986

Post by perceval »

i find one of 1986's comment above instructive on how we build bad habits that are hard to shake off:

he commented:

1986 wrote:I'm pretty sure this is the right move right now, Just keep pushing him until its over,
these stones are dead, i read it out,
but I'm still trying to get something out of them, something!


and then he got a stream of stronger player yelling aji keshi at him ...

but lo and behold: it might work at the very least he will got a bigger corner and a possibility of a juicy ko.

The thing is trashing with a dead group might be the best course of action at this level (not sure i would have avoided the trap myself) when it might work.

Then at some point it doesnt work anymore and you have to stop doing something that worked very nicely before and replace it with something else: a good illustration that your level might drop when you learn (because if you stop doing that against 9k you might end up losing a bit more games)
In theory, there is no difference between theory and practice. In practice, there is.
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Re: 115 - robinz v. 1986

Post by robinz »

Click Here To Show Diagram Code
[go]$$Bcm167 Prisoner Count :w1: :b4:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O . |
$$ | . . X , X . . . . , O . X . X X X O . |
$$ | . . X X X . . . . . . . X O O O X O . |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X 1 . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ +---------------------------------------+[/go]


Hey, now you're trying to give yourself 3 extra prisoners from nowhere! :lol: (Am joking, although you did - I know how easy it is to make mistakes :))

Well, seeing Ed's question about my last move rattled me a bit - and I admit that it could still prove to be a very bad move. But right now, I feel it's doing quite well for me. After this move, and white's forced response at S1, white is still at least 6 plays away from capturing me, counting approach moves necessary thanks to the shortage of liberties T2 is creating (and may also have to win a ko over T2, although since he won't take it until it's atari, it's hard to see how I can have any ko threat he won't happily ignore). And I think I am only 5 net plays away from capturing him, although this is much trickier to calculate. I'll probably remove a liberty next, just to be on the safe side - and even then I'm far from certain I haven't missed something.

This fight is an example of both why I love go, and why I hate it because I suspect I will never be good enough at it to know what is going on in a complicated situation like this :scratch:
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Re: 115 - robinz v. 1986

Post by 1986 »

Click Here To Show Diagram Code
[go]$$Wcm168 Prisoner Count :w4: :b1:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O . |
$$ | . . X , X . . . . , O . X . X X X O . |
$$ | . . X X X . . . . . . . X O O O X O . |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O 1 . |
$$ +---------------------------------------+[/go]


@robinz: my bad, i thought the 3 extra prisoners would give me the edge i need lol

Everybody know this is the only move, the only question is where is robinz going to play next, if this was guess the next move i would say p4 or p3, 

but im bad at guessing where robinz would play otherwise i would have already won by resgination :) 

but hey practice makes perfect *thinking*
 
standing still means going backwards
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Post by EdLee »

1986,
1986 wrote:Everybody know this is the only move
Go is full of surprises. You read ez4u's notes after the game. :)
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Re: 115 - robinz v. 1986

Post by robinz »

Click Here To Show Diagram Code
[go]$$Bcm169 Prisoner Count :w4: :b1
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O . |
$$ | . . X , X . . . . , O . X . X X X O . |
$$ | . . X X X . . . . . . . X O O O X O 1 |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O O . |
$$ +---------------------------------------+[/go]


As I said last time, I'm not 100% sure this is necessary, but I don't want to leave anything to chance here. I can give my opponent sente and still have a chance of winning what will then be a close game, or blunder here and lose on the spot. I'm unable to read this fight well enough to know if I need another move or not, so I'm taking the safe option.
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Re: 115 - robinz v. 1986

Post by 1986 »

Click Here To Show Diagram Code
[go]$$Wcm170 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O . |
$$ | . O X X . X X X . . . . . X . X O O 1 |
$$ | . . X , X . . . . , O . X . X X X O . |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O O . |
$$ +---------------------------------------+[/go]


this should be interesting, a ko fight, now i gotta line up some major ko threats to give me some good moves elsewhere
standing still means going backwards
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Re: 115 - robinz v. 1986

Post by ez4u »

Obs:
Consider the impact from the choice of where to play B169:
1. 1, 2 = 169, 170 as in the actual game...
Click Here To Show Diagram Code
[go]$$Bc :b9: @ T12
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 3 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O 2 |
$$ | . . X , X . . . . , O . X 5 X X X O b |
$$ | . . X X X . . . . . . . X O O O X O 1 |
$$ | . . . O . . . . . . . O O X X O O O 7 |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 4 X a X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . 6 O O 8 |
$$ +---------------------------------------+[/go]


2. Better alternative for Black 1
Click Here To Show Diagram Code
[go]$$Bc :w4: @ T13, :b9: @ T12
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 1 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O 2 |
$$ | . . X , X . . . . , O . X 5 X X X O . |
$$ | . . X X X . . . . . . . X O O O X O 3 |
$$ | . . . O . . . . . . . O O X X O O O 7 |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 6 X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . 8 O O . |
$$ +---------------------------------------+[/go]

In the alternative variation, White has to immediately take the ko or Black will connect and simply win. This is unnecessary in the actual game. Black loses a move here through the choice of B169.

Note that after White fills an internal liberty with "a" in the upper diagram, "b" becomes an internal ko threat for White. If White tried it before playing "a", Black would simply connect the ko and win the fight with three liberties to two.
Dave Sigaty
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- Marcus Aurelius; Meditations, VIII 21
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Re: 115 - robinz v. 1986

Post by robinz »

Hmm - I may be able to move in a few hours, but it is most likely that I will leave this for a while; there is much to ponder. (And I'm busy this weekend, playing in my first real-life go tournament, so may not get much time then.)

I desparately need to find something here. The whole position is a horrible mess of kos and potential kos, but according to my reading, I'm screwed unless I can find something. The best I can get is a ko over T12/13, which is very favourable in the sense that it's a 2-step ko for white and that I take first - but white has at least 4 big ko threats on top, whereas I appear to have virtually none. Clearly I can't lose the ko, but nor can I win it and give up the top and hope to have a chance in the game. I'm getting quite disillusioned as I read this out looking for resources (I will admit I'm actually physically playing out sequences rather than reading in my head - this is far too hard for me otherwise, as well as too fascinating to pass up the chance to :D) - but it's complicated enough that I feel there might just be *something* there. I'm basically trying to see if I can engineer enough local ko threats to escape with my group - although I admit that this seems unlikely. There's also a chance I can set up another ko involving P5 and hope to gain something out of the fact that white needs to win this ko and that at T2 in order to actually capture me. Put like that, it sounds like that should work, but I've tried playing it out and I was far from convinced that it did.

It's all a horrible - if absolutely fascinating - mess, and I need to do a lot more reading :study:

If I don't find anything, I'll probably come back on Monday and play out a few obvious moves, and then resign assuming 1986 doesn't do something stupid.
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Re: 115 - robinz v. 1986

Post by 1986 »

Good luck at your tournament Buddy!
standing still means going backwards
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Re: 115 - robinz v. 1986

Post by robinz »

I'm very sorry - I've found no time to think about this position (or even log onto L19) all week. I promise I'll be able to make a move this weekend.

I scored 4 wins and 2 losses in the tournament, including several fun and ridiculously fighty games, so that was good :D
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Re: 115 - robinz v. 1986

Post by Sevis »

For myself, mostly.
I want to make a prediction on the ko...

Click Here To Show Diagram Code
[go]$$Bcm171 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 5 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O 7 |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X 3 X X X O 8 |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O 1 |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 2 X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . 4 O O 6 |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Bcm179 Prisoner Count :w7: :b4:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X 2 |
$$ | . O X O O O O . . . . . . . X . X O X |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X X X X X O O |
$$ | . . X X X . . . . . . . X O O O X O 1 |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O O X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


Squares are white ko threats, triangles are black...

Click Here To Show Diagram Code
[go]$$Bcm181 Prisoner Count :w7: :b5:
$$ +---------------------------------------+
$$ | . . . . . . . . S . . O S S S . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . T . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O T T O . O X . . X |
$$ | . T O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O . |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X X X X X O O |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O T . . . O O X . X X |
$$ | X X X O X O . T T . O . . O . O X X . |
$$ | . . S X X O . . . . . . . . . O X O X |
$$ | . . S . . . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


I'm not sure whether B13 and H16 really are big enough, though.... C17 could be a threat, but it would be risky, and would be smaller. But, heck, anything is smaller... I think K4 is black's best bet.
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Re: 115 - robinz v. 1986

Post by robinz »

Right, with my apologies once again, let's get this show back on the road! :rambo:

Click Here To Show Diagram Code
[go]$$Bcm171 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O . |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X 1 X X X O . |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O O . |
$$ +---------------------------------------+[/go]


OK, so where was I before the long break? Oh yes, I'd convinced myself that I'd messed up somewhere along the line, and that my position was absolutely hopeless unless I found some cunning resource, somehow. Came back to the game tonight, tried a few "cunning" things, and found that they basically didn't work, although they might be worth a try if my position really is hopeless, to see what my opponent comes up with.

But then I took a step back, and looked at "obvious" moves again, such as the one above. When I did, I realised that it was a total mystery to me why I thought that the resulting ko was in any sense bad for me. After the following (more or less a one-way street, if white decides to continue the capturing race, although move orders can vary):

Click Here To Show Diagram Code
[go]$$Bcm171 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 3 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O 7 |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X 1 X X X O 5 |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 2 X 6 X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . 4 O O . |
$$ +---------------------------------------+[/go]

- the ko starts, but what precisely was I afraid of? White still needs three more moves to capture me, and of course he can't afford to fill the ko (or he leaves himself in atari). He makes a big ko threat on top, let's say - I respond, and then what does he do? If he retakes the ko, I can even afford to simply remove a ko threat on top, and he is then still two moves away from capturing me. All he can do is make another, smaller, ko threat - of which he has several, C2 in particular will be mighty annoying, as losing the lower-left corner would still be game-losing. But I think I can see ways to resist and perhaps capture the C5 group first if it comes to that - even if not, I can at least force him to find some accurate moves before calling it a day.

But this position is still mightily confusing me, and I'm sure I'm still missing something key. Oh well, I can't stand the suspense any more, so let's just play it out and see what happens :lol:
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Re: 115 - robinz v. 1986

Post by ez4u »

Obs:
robinz wrote:Right, with my apologies once again, let's get this show back on the road! :rambo:

Click Here To Show Diagram Code
[go]$$Bcm171 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O . |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O . |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X 1 X X X O . |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O . X . X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . . O O . |
$$ +---------------------------------------+[/go]


OK, so where was I before the long break? Oh yes, I'd convinced myself that I'd messed up somewhere along the line, and that my position was absolutely hopeless unless I found some cunning resource, somehow. Came back to the game tonight, tried a few "cunning" things, and found that they basically didn't work, although they might be worth a try if my position really is hopeless, to see what my opponent comes up with.

But then I took a step back, and looked at "obvious" moves again, such as the one above. When I did, I realised that it was a total mystery to me why I thought that the resulting ko was in any sense bad for me. After the following (more or less a one-way street, if white decides to continue the capturing race, although move orders can vary):

Click Here To Show Diagram Code
[go]$$Bcm171 Prisoner Count :w4: :b2:
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 3 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O 7 |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X 1 X X X O 5 |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 2 X 6 X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . 4 O O . |
$$ +---------------------------------------+[/go]

- the ko starts, but what precisely was I afraid of? White still needs three more moves to capture me, and of course he can't afford to fill the ko (or he leaves himself in atari). He makes a big ko threat on top, let's say - I respond, and then what does he do? If he retakes the ko, I can even afford to simply remove a ko threat on top, and he is then still two moves away from capturing me. All he can do is make another, smaller, ko threat - of which he has several, C2 in particular will be mighty annoying, as losing the lower-left corner would still be game-losing. But I think I can see ways to resist and perhaps capture the C5 group first if it comes to that - even if not, I can at least force him to find some accurate moves before calling it a day.

But this position is still mightily confusing me, and I'm sure I'm still missing something key. Oh well, I can't stand the suspense any more, so let's just play it out and see what happens :lol:


Robinz is probably going to hate me by the time I get done with all my comments, but I find this game quite fascinating... ;-)

The key point that is being missed right now is that Black can win the ko by capturing it and connecting. That means that each play filling a liberty is an internal ko threat for Black! Therefore Black should immediately start the ko and then use each liberty-filling play as a ko threat.
Click Here To Show Diagram Code
[go]$$Bc Correct Order?
$$ +---------------------------------------+
$$ | . . . . . . . . . . . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . . O X X O . . X X X |
$$ | . . O . O . . . . O . . O . O X O O 1 |
$$ | . . O X . . . . . . . . . . . X X X O |
$$ | . O X O O O O . . . . . . . X . X O 3 |
$$ | . O X X . X X X . . . . . X . X O O O |
$$ | . . X , X . . . . , O . X a X X X O c |
$$ | . . X X X . . . . . . . X O O O X O X |
$$ | . . . O . . . . . . . O O X X O O O . |
$$ | . . O . X X X X . X . . . O X O X O O |
$$ | . O O . X O O X O . . . . O X X X X O |
$$ | X X O X . . . O X X . . O . O X . X O |
$$ | . . X O O O . . O , . . . O 2 X d X X |
$$ | X X X O X O . . . . O . . O e O X X . |
$$ | . . . X X O . . . . . . . . . O X O X |
$$ | . . . . . . . . . . . . . . . b O O . |
$$ +---------------------------------------+[/go]

Next White plays a ko threat (the 1st), Black answers, and White takes the ko. Now Black fills a liberty at "a" as a ko threat. White answers at "b" and Black retakes the ko. White makes another external threat (the 2nd), Black answers, and White takes the ko again. Now Black plays "c" and White has to answer at "d". Black retakes the ko. White has to make another ko threat (the third). Black has yet to make an external ko threat. If all the filling in is done first (as shown in robinz's diagram above) then Black needs an external threat immediately. It is true that White has to ignore a couple of Black threats to win the ko. However, the ko is being fought within Black's original territory and is worth more than 70 points. Black must win the ko. White can win the game by gaining enough compensation elsewhere. It is very important that Black have some flexibility to answer some White threats.
Dave Sigaty
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