Turton doubling

A piece A moves along a line across a square (critical square) allowing another piece B of the same colour to move to the critical square. Then, B moves on the line in the opposite direction, being supported by A. B is stronger than A.

The difference from Loyd's clearance is that the critical piece preserves its supportive power of the other piece.

Three different forms are recognized:

(Ordinary) Turton Doubling. Two like motion pieces are of different strength. The weaker one first makes an anti-meta-critical move, and subsequently the stronger one comes in front.
Loyd-Turton Doubling. Two like motion pieces are of different strength. The stronger one first makes an anti-meta-critical move, and subsequently the weaker one comes in front.
Brunner-Turton Doubling. Two like motion pieces are of the same strength.

Alias: Turton.

Abdurahmanović, Fadil

Ellinghoven, Bernd

feenschach, 2009

1st Prize