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Subject: Re: CCT5 - Crafty perspective

Author: Rolf Tueschen

Date: 06:17:36 01/21/03

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On January 21, 2003 at 09:09:49, Ricardo Gibert wrote:

>On January 21, 2003 at 08:52:02, Rolf Tueschen wrote:
>
>>On January 20, 2003 at 23:00:55, Ricardo Gibert wrote:
>>
>>>On January 20, 2003 at 21:57:38, Robert Hyatt wrote:
>>>
>>>>On January 20, 2003 at 21:32:22, Ricardo Gibert wrote:
>>>>
>>>>>On January 20, 2003 at 20:44:21, Robert Hyatt wrote:
>>>>>
>>>
>>>[snip]
>>>
>>>>>>Round 6  Crafty vs Searcher
>>>>>>
>>>>>>A near disaster for the first game of the second day.  The same d4 opening
>>>>>>led to a similar position, but things did not go very well here.  First score
>>>>>>out of book was -.42, which was typical for every 1. d4 game crafty played as
>>>>>>white. But it was able to pull that up quickly normally.  10 moves out of book,
>>>>>>the score hadn't changed, showing that searcher was playing very well and with
>>>>>>a reasonable amount of understanding of the position.
>>>>>>
>>>>>>Finally by move 24, Crafty was back to a slightly + score, and this held until
>>>>>>it started dropping as it misjudged the queen/rook attacking in the center.  At
>>>>>>move 32, the score was -.68 after 16 plies.  at move 35, the score was -1.5, at
>>>>>>move 40 -2.0, -2.5 at move 50, -3 at move 60,  and at this point Crafty dug
>>>>>>in its heels and pulled the score back to -2.3 where it stayed for a long
>>>>>>while.  But it slowly traded pawns, and the score started swinting back.  By
>>>>>>move 80, it was -2.0 again, -1.5 by move 85, -1.0 by move 95,  and it finally
>>>>>>reported a draw score at move 102.  Of all the games it played, this was a
>>>>>>really nice effort as it showed a lot of understanding about king rook and pawn
>>>>>>endings, something I have worked on a lot over the years.
>>>>>
>>>>>
>>>>>I find your last sentence surprising. Crafty was very lucky in this game that
>>>>>Searcherx did not play 62...Re8 62.Kxg3 Rb8 winning easily.
>>>>>
>>>>>
>>>>
>>>>Crafty says if you play Re8 it just plays Rb7 immediately, not Kg3.
>>>>
>>>>Score doesn't change much...
>>>>
>>>>It may be overlooking something, but it isn't going to let black get
>>>>the rook behind the pawn...
>>>>
>>>>Maybe we are at the wrong move?  IE you have two move 62's above.
>>>>Do you mean 61. Re8?
>>>
>>>
>>>Yes. 61...Re8 62.Kxg3 Rb8 was my intention.
>>>
>>>
>>>>
>>>>Going back to move 61, and playing Re8 Kg3 Rb8 I get Rd4 and Rb4.  White
>>>>loses one of the pawns on the h file, but only one.  It isn't clear to me,
>>>>without a lot of study, how black makes progress.  The pawn is blockaded, so
>>>>the black rook is stuck on the b file unless it gives check.  The black
>>>>king can't abandon the kingside or white will eat the g pawn and the hpawn
>>>>should be enough to force the trade of the rook and a draw...
>>>
>>>[D]8/1p1R2pk/5p2/7P/7P/5Kn1/4r3/8 b - - 0 60
>>>
>>>61...Re8 62.Kxg3 Rb8 63.Rd4 b5 64.Rb4 Kh6 65.Kg4 Rb7 66.Kh3 Kxh5 67.Kg3 g6
>>>68.Kh3 f5 69.Kg3 Rb6 70.Kh3 Rc6 71.Rb3 Rc4 is a prosaic and convincing win.
>>
>>A comparable position is available with many different continuations. One is
>>your 61-Re8 others I pointed out in
>>http://www.talkchess.com/forums/1/message.html?278466
>>The point is that you always winn with the f/g free pawns if they are so good
>>combined. No need to know the rule of the R behind the pawns because you give
>>the b pawn away.
>>
>>Kind regards,
>>Rolf Tueschen
>>
>>
>>
>
>
>Even though it is later given away, it handcuffs the defense giving time to make
>preparations before giving up the b-pawn to win on the K-side, so it is still an
>important tool.

No doubt about it. But I was looking for the programmers and you said yourself
that this is difficult to program. So I had a look at totally normal chess,
calculable or countable if you like. And this position with the combined pawns
is won and that is the whole thing. I meant the argument of the "difficult"
Re8-b8 is even not necessary.

Rolf Tueschen


>
>[snip]



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