Why is this position evaluated so?

Technical questions regarding Openings, Middlegames, Endings etc.
soheil_hooshdaran
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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Sun Jun 11, 2017 9:31 am

Why doubling Rooks on the d-file is easier for White in:

soheil_hooshdaran
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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Sun Jun 11, 2017 10:16 am

Why would 38.Kh2 be better than 38.Qd6+ in:

Roger de Coverly
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Re: Why is this position evaluated so?

Post by Roger de Coverly » Sun Jun 11, 2017 11:03 am

soheil_hooshdaran wrote:Why would 38.Kh2 be better than 38.Qd6+ in
If the Queen is on d6, Black has a threat of playing .. Ra1 and .. Qb1 with a mate threat himself. Playing Kh2 gives Black the problem of finding a decent move. If there's a time control at move 40 and either player is short of time, that's another reason to make Black do the thinking.

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Christopher Kreuzer
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Re: Why is this position evaluated so?

Post by Christopher Kreuzer » Sun Jun 11, 2017 11:16 am

In addition, the Black king currently can't move. By playing Qd6+, White allows the Black king to escape to g7, and gives the Black rook the chance to come to f8 to defend f7. Roger is right that Black is very short of moves. The knight and king cannot move, the rook needs to defend the back rank, and Black has no checks. One plan is to try and exchange queens with a check on a1, but White putting the king on h2 avoids that.

Having said all that, Black does have the obvious reply Qe6. But then Whie just exchanges queens and plays Rd6 and will be two pawns up soon, with a winning position. Maybe Black has to play something like Re8, when White can now play Qd6+ and win the pawn on c6, again with a winning position (though Ne5 is even stronger).

Another line is Kh2 Rc8 Qd6+ Kg7 Ne5 Rf8 Qxg6+.

Though hang on. Doesn't Qd6+ and Ne5 win without the need to play Kh2? Maybe Black runs away to h6 in that line and White has no mate and then gets mated in turn if not careful?

soheil_hooshdaran
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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Sun Jun 11, 2017 12:59 pm

That's right. After Ne5 Nf6, White can't take of f7 because he gets mated if he does.

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Christopher Kreuzer
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Re: Why is this position evaluated so?

Post by Christopher Kreuzer » Sun Jun 11, 2017 1:17 pm

Ah, Qd6+ Kg7 Ne5 Nf6 is clever! Rxf7+ Qxf7 Nxf7 Ra1+ Kh2 Ng5+ Kh3 Nf2+ Kh2 Rh1#!

Difficult to visualise that rerouting of the Black knight from g8 to f2 without concrete analysis like that. Reminds me of this semi-problem I sort of composed here:

http://www.ecforum.org.uk/viewtopic.php?f=2&t=2283

('Rook and Knight Perambulations')

soheil_hooshdaran
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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Wed Aug 01, 2018 5:18 pm

why is White better in?
?

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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Thu Aug 02, 2018 11:23 am

Why is Black "clearly" better in:

Roger de Coverly
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Re: Why is this position evaluated so?

Post by Roger de Coverly » Thu Aug 02, 2018 11:37 am

soheil_hooshdaran wrote:
Thu Aug 02, 2018 11:23 am
Why is Black "clearly" better in:
Space and a bind on the position. But I'm not sure I totally share the writer's confidence.

If it's Black to move, or even if it isn't, .. Nd4 looks annoying.

soheil_hooshdaran
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Re: Why is this position evaluated so?

Post by soheil_hooshdaran » Mon Aug 27, 2018 6:51 pm

Where is White's advantage?

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IM Jack Rudd
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Re: Why is this position evaluated so?

Post by IM Jack Rudd » Mon Aug 27, 2018 7:15 pm

Better pawn structure and safer king.