Hello all,
This posting is divided into various parts. You can jump to the headings of the
sections by search/find for **, a pair of asterisks
.
** Positional evaluation of the problem
.
White: 2 pawn islands and temporarily a piece down. The c2 pawn is attacked and
undefended, but as white is a piece down this is not the most important feature
of the position. The king on h1 has almost no defensive support, however
despite the activity of the black pieces they are not yet coordinating to
create threats. The queen on f7 is involved in the attack on the black king.
She is not threatened by the black g7 rook, the f6 bishop has paralysed that
rook with a pin to the black king. There is a mutual x-ray attack on the
f-file, the 2 queens are only separated by the white f6 bishop, which is
therefore pinned to the white f7 queen. The a1 rook would like to join in with
the kingside attack, but the best entry point of the f1 square is denied it due
to the black f4 queen. The h5 rook is very aggressively placed, creating
tactical opportunities against the black kingside. The f6 bishop is pinning the
black g7 rook to the black king, which ensures white can win back an exchange
with check if necessary
.
Black: 3 pawn islands and temporarily a piece up. The king is trapped without a
move by his own defending rooks and h-pawn, not a happy situation. The queen on
f4 seems actively placed, but is not coordinating with the rest of the black
forces, and as such is not showing her full strength. The doubled rooks on the
g-file give the appearance of activity with threat, but this is an illusion.
The pin of the g7 rook combined with the attack from the white f7 queen ties
down the g8 rook to defending the pinned g7 rook. In essence, both of the black
rooks are immobilised. The bishop on c5 is pointing in the general direction of
the white king, but is at the moment blocked from influencing the position by
the black d4 knight. The d4 knight is centrally located, a good square for a
knight, threatening to capture the white c2 pawn, or further advance to the e2
square
.
** Proposed solution to WAC128
.
The black forces give the impression of activity, but there is no coordination
between them, either for attacking or defensive purposes. The 5 black pieces
are about to be outplayed by just 3 white pieces
.
White takes full advantage of the pin of the black g7 rook with, 1. Qg6, which
also takes advantage of a pin from the white h5 rook on the black h7 pawn. The
threat is simple, Qxh7+ mate. There is only one move available for black to
prevent mate, 1. ... Qxf6. By giving up the queen black has destroyed the
powerful pin on the g7 rook, which is then offering a defence to the weak h7
pawn. White no longer has a mating attack, but after, 2. Qxf6, it is a winning
material advantage for white. Somewhat annoyingly for black, the white queen is
now pinning the black g7 rook, there is still more unravelling for black to
perform. The game needs to be converted to a win by white, but it is definitely
a win
.
A couple of immediate losing attempts for black could have been,
1. Qg6 Rf8 2. Qxh7+ mate. Or,
1. Qg6 h6 2. Rxh6+ Qxh6 3. Qxh6+ mate, in each case the bishop pin paralyses
the g7 rook
.
** Condensed proposed solution
.
1. Qg6 Qxf6 2. Qxf6
.
** Other tactical variations considered, and rejected
.
The attempted brutal mating attack with, 1. Rxh7+ Kxh7 2. Qh5+, fails to a
backward intervention from the black queen with, 2. ... Qh6. Backward
interventions are easy to overlook, especially when for most of the game the
army has been planning on moving forward. White is now a piece and rook down
without any further attacking ideas, this is totally lost
.
The materialistic, 1. Bxg7+ Rxg7, is not as obviously decisive as the proposed
solution. The white attack has dissipated, and while, 2. Qe8+ Rg8 3. Qxe5+ Qxe5
4. Rxe5 Bb6 5. c3, Nc6 6. Rxb5, leaves white with a nominal 2 pawn advantage,
there is still work needed to be done
.
** Alarm bells
.
1. Activity of pieces is important, but it is the level of coordination which
determines the strength of a position
.
2. An active minor piece can often be of greater value than an opposing
disabled rook. While winning an exchange is good housekeeping, sometimes a
greater reward can be found by declining a material gaining capture
.
3. The point of the pin is to paralyse
.
Paul Benson.
. -----Original Message-----
From: Richard Dinger - Email Address: rrdinger@xxxxxxxxxx
Sent On: 22/06/2015 23:27
Sent To: chess - Email Address: blind-chess@xxxxxxxxxxxxx
Subject: [blind-chess] Problem WAC127
Problem WAC 128
White to move
FEN:
6rk/
1pp2Qrp/
3p1B2/
1pb1p2R/
3n1q2/
3P4/
PPP3PP/
R6K
w - - 0 1
Short Algebraic Problem Setup:
White: Kh1, Qf7, Ra1, Rh5, Bf6, Pa2, Pb2, Pc2, Pd3, Pg2, Ph2
Black: Kh8, Qf4, Rg7, Rg8, Bc5, Nd4, Pb5, Pb7, Pc7, Pd6, Pe5, Ph7
