Charles Gilman wrote on Thu, Apr 15, 2004 08:27 AM UTC:Good ★★★★
Another approach to castling might be the following one, used in my
Ecumenical Chess
(http://www.chessvariants.com/large.dir/ecumenical-chess.html), of which
the large-board arrays have King and Rooks on different ranks.
Castling requires that the King has not left the middle two files, the
Rook involved has not left its own and the adjacent file, neither has
left
the back two ranks, and both are on the same rank. The King moves 1/4 of
the total number of files (3 in the largest, 2 in the others) towards the
Rook, and the Rook moves to be adjacent to the King on the inner side.
Note that this takes the King off its group of four squares and so
disallows castling with a second Rook.