1001 GoGoD games for your Coffee Break #29(14 February 2013)

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TMark
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1001 GoGoD games for your Coffee Break #29(14 February 2013)

Post by TMark »

This game comes from the final of the 36th Oza in 1988 between Kato Masao and Takemiya Masaki, both 9dan. Black, for all his reputation as a happy-go-lucky, easy going fellow, got into time trouble and took back a ko without making a threat, so he lost by forfeit. Ironically, with proper play Takemiya would have won the game by 0.5 points.

Best wishes.

No aji, keshi, kifu or kikashi has been harmed in the compiling of this post.
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by macelee »

First of all, white would definitely win this ko, because of B15 and many threats there. Black would lose by 0.5 unless there's something inside the territory forcing white to fill one point. Can any one show a sequence what black can do, say after 'a'?

Click Here To Show Diagram Code
[go]$$Bc What happens after 'a'?
$$ +---------------------------------------+
$$ | . . X O O . . . . . . . . O X X X . . |
$$ | . . X X O . . . . . O a . O O X X . . |
$$ | . . X O . O . O . . . . X O O O X . . |
$$ | . . X O . . O X O O . X . O X X O X . |
$$ | . . X O . . O X 4 O O X . O 1 X O . . |
$$ | . X O O O O X X X X X O O O O X X . . |
$$ | . X O X X O X O . X O 2 O 3 O O X . X |
$$ | X X X X O O O X X X X O O X X O X . O |
$$ | X O O X X O O O O X X X X X O X . . . |
$$ | X O . O X O X X X X O X X O O X X X X |
$$ | O O O O X O O O O O O X . X O O X . . |
$$ | . . X O O . O O . . O O X X O . O X X |
$$ | . . . O X O O X O O X O X O . O . O . |
$$ | . . O O X X X X X O X X X O . O O O . |
$$ | . . O X X X O O O O X X . X O O X X X |
$$ | . . O O X X X X X X . X . X X X X O X |
$$ | . O O X X . . . . . . . X O O X O O O |
$$ | O . O X . . . . . . . X . X O O . O . |
$$ | . O X X . . . . . . . . X X X O O . . |
$$ +---------------------------------------+[/go]
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by kivi »

'a' doesn't work but gives ko threats (also J17), so I thought "proper play" meant winning the ko.
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by macelee »

That's a good point. White has 6 ko threats, 4 at B15, 1 at S15 and 1 at M1. Black has J8, P7 and S1. Black needs 4 more ko threats around M18 to be able to win the ko. The situation is more complex than it appears. And I suppose the players needed to read this in 1 minute byo-yomi.
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by John Fairbairn »

I thought I would check back on this. It turns out that both the original Kido commentary and our note are ambiguous, though in slightly different ways. But the explanation points up an interesting aspect. The guys in the press room had concluded with remarkable accuracy that Black would win by half a point after Black 165 - exactly 100 moves before the end. This sheds some light on claims about the ability of Jowa et al. to know the result that early, and also on Michael Redmond's recent attempts to improve his endgame.

The ambiguity arose because the text says: "Black cut off two white stones with 163 and 165 and the press room came to the conclusion that Black was half a point ahead. However, Takemiya answered the ko capture of White 264 by taking the ko but without making a ko threat." It was not quite as cause-and-effect as perhaps implied.
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by Mikebass14 »

So you mean that actually white was winning anyway at 264, and that black probably lost a point somewhere over the last 100 moves?
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by macelee »

Because this thread was brought back to life, I spent a few minutes to work out a possible sequence to continue. The result is indeed B+0.5

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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by skydyr »

Looking back at this game, you have to love the gigantic center territory Takemiya made with his moyo, regardless of the result.

Also, at least when I've heard Takemiya speak, he spoke of not remembering things in the past, like his previous games or what he ate for breakfast that day. I wouldn't be surprised if this extends to who made the last ko threat, at least on occasion.
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by Mikebass14 »

Thanks for the analysis, macelee, and sorry to bring back a zombie thread. I saw February, didn't pay attention to the year or day, and thought the discussion was recent. :-?
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Re: 1001 GoGoD games for your Coffee Break #29(14 February 2

Post by Bonobo »

Mikebass14 wrote:[..] sorry to bring back a zombie thread [..]
It’s never a bad idea to remind us all of TMark :-)
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