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Subject: Re: Not so fast

Author: Vincent Diepeveen

Date: 14:29:33 09/17/01

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On September 17, 2001 at 14:31:30, Robert Hyatt wrote:

Bob, take it from an FM, after gxf4 the game is very complex.
yes it's lost, but it's *not* easy. And suppose you make a passer
mistake, well in that case you still draw it, has happened before...

However in the case of f3 e3 then it's a simplistic win. With Bh5
you get the same endgame but even better at the board because you threaten
to create a mating attack after which it's completely game over in the
endgame with a piece up!

>On September 17, 2001 at 03:36:16, Vincent Diepeveen wrote:
>
>>On September 16, 2001 at 22:40:59, Robert Hyatt wrote:
>>
>>>On September 16, 2001 at 16:30:27, Bruce Moreland wrote:
>>>
>>>>On September 16, 2001 at 16:15:32, Vincent Diepeveen wrote:
>>>>
>>>>>On September 16, 2001 at 00:36:22, Bruce Moreland wrote:
>>>>>
>>>>>>Vincent emailed me and asked me to run these.  I ran them on a quad 450 Xeon.
>>>>>>
>>>>>>[D]8/p4bpk/7p/3rq3/3Npp2/PPQ3P1/3R1PKP/8 w - - 0 1
>>>>>>
>>>>>>I get gxf4 until ply 10, after which there is a switch to b4, which is a bad
>>>>>>move.  This fails low to -3.88 in ply 11, and gxf4 comes back with a score of
>>>>>>-2.48.
>>>>>>
>>>>>>Later in ply 11, f3 pops up with a score of -2.33.
>>>>>>
>>>>>>Up to here takes 89 seconds.
>>>>>>
>>>>>>f3 sticks until ply 14, at which point if fails low to -4.24, and gxf4 comes
>>>>>>back with a score of -3.21, resolving after about 1/2 hour.
>>>>>>
>>>>>>In ply 15, gxf4 fails low again, and the hour ended with no resolution.  It was
>>>>>><= -3.46.
>>>>>>
>>>>>>[D]8/p4bpk/7p/3rq3/3Npp2/PPQ2PP1/3R2KP/8 b - - 0 1
>>>>>>
>>>>>>In this one, I have exf3+, with a score of +2.35 in ply 10.  After 16 seconds,
>>>>>>in ply 10, it finds Bh5, failing high to +2.80.
>>>>>>
>>>>>>Ply 11 was uneventful, but in ply 12, Bh5 failed high to +4.24.
>>>>>>
>>>>>>The score creeps up slightly, and the last score I got in the hour was +4.99,
>>>>>>ply 15, after about 45 minutes.
>>>>>>
>>>>>>I'll run the first one again all night and see what happens.
>>>>>>
>>>>>>bruce
>>>>>
>>>>>thanks!
>>>>>
>>>>>It confirms already what i suspected. f3 is losing
>>>>>way harder than alternatives!
>>>>>
>>>>>I do not understand why ferret needs a ply more to get -4.24 for f3
>>>>>than when after f3 is getting played. Possible to shine any light onto
>>>>>this?
>>>>
>>>>I don't see that you can draw that conclusion at all, especially in light of
>>>>this:
>>>>
>>>>    ply  milliseconds score           line
>>>>no   17  27657860   -433  -1221224784 gxf4 Qxf4 Kh1 Rh5 f3 exf3 Nxf3 Rh3 Rf2
>>>>                                      Bd5 Rg2 g5 Qd3+ Qe4 Qxe4+ Bxe4 Nd2 Bxg2+
>>>>                                      Kxg2 Rd3 Ne4 Rxb3 a4 Rb4 Nc5 Rb2+ Kg3
>>>>                                      --
>>>>no   17  41753610   -499    666953819 gxf4 Qxf4 f3 Bh5 Kf1 e3 Re2 Rxd4 Rxe3
>>>>                                      Rd1+ Re1 Qxf3+ Qxf3 Bxf3 Rxd1 Bxd1 b4 Kg6
>>>>                                      Kf2 Bc2 Ke3 Kf5 b5
>>>>no   17  50832840   -494  -1178700567 f3 Bh5 g4 e3 Rd1 Bg6 Qc4 e2 Re1 Rxd4 Qxe2
>>>>                                      Qxe2+ Rxe2 Rd3 b4 Rxa3 h4 Bd3 Rd2 Rc3 Kh3
>>>>
>>>>Column 4 (node count) is broken and should be ignored.
>>>>
>>>>gxf4 failed low to -4.99 in ply 17, and f3 overtook it at -4.94.  So mine would
>>>>play f3 after 50,832 seconds.
>>>>
>>>>bruce
>>>
>>>
>>>This is part of the problem in trying to compare anything.  Vincent is assuming
>>>way too much.  namely that f3 is worse.  Based on some short searches from his
>>>program.  These need many plies to see what is _really_ going on.  And trying to
>>>make a point that f3 was horrible (as played by DB) is a mistake without some
>>>real evidence.  Your program seems to suggest the opposite, that f3 was the
>>>_right_ move...
>>
>>May i note that after f3 as a human i win blindfolded the endgame with e3
>>as this wins a piece and goes to KRB for black versus KR for white.
>
>And may I note that after gxf4 _I_ could win _that_ game blindfolded.  Both
>are lost.  And whether f3 is worse than gxf4 is still undecided.
>
>
>>
>>Kasparov of course didn't even look to Bh5 because e3 won blindfolded
>>for him.
>>
>>Note at 16 ply score here for gxf4 is -3.975 versus f3 was lower than -5.xx here
>>
>>So the best proof i have is the game!
>>
>>I'm pretty amazed that many programs till today have a king safety which
>>is not adequate for this position to see that f3 bh5 is getting simply
>>and soon mated.
>>
>>Best regards,
>>Vincent



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