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Something rather easier this time. Colin Sydenham quotes this problem in
his recent personal collection (highly recommended – see under Members’
Publications), describing it as one of the finest British two-movers of
the last quarter of the 20th century. Solvers should note the cyclic
effect contained in the four thematic variations.
The solution will appear here on Friday 15th July.
The problem is a brilliant example of a dual avoidance cycle following interferences. The key is 1.Sh5, threatening 2.g4, and the c4 knight can defend by opening a rook line. Each of its four moves closes two black lines, but each time a compensating element introduced by the knight's arrival prevents White from exploiting one of the errors.
1...Sb2 (closes b8-b1 and a1-f6. Guard of d3 prevents 2.d4) 2.Rxf7 1...Se5 (closes a1-f6 and b8-g3. Guard of f7 prevents 2.Rxf7) 2.Sg3 1...S4d6 (closes b8-g3 and a6-e6. Closure of c6-f6 prevents 2.Sg3) 2.Qd7 1...S4b6 (closes a6-e6 and b8-b1. Guard of d7 prevents 2.Qd7) 2.d4
There are three by-play variations, 1...gxh5 2.Rg5, 1...Qf4, 2.Rxf4 and 1...Qg3 2.d4, 2.dxc4 or Sxg3.
Don worked on the idea for two years! Chris Reeves, who was the judge who awarded the problem its prize, found a way to eliminate a knight takes pawn key.
Any comments or questions on this problem should be addressed to
Michael McDowell using the ‘Contact’ item in the menu on the left.