[Retros] 50-moves draw revisited

[Pastmaker at aol.com]

It is the case that after a capture or a pawn move the board array can never 
be restored by valid chess moves to any position that existed prior to that 
capture or pawn move, which seems to be a perfectly reasonable way to measure 
"progress" in an over-the-board game. 

It is also the case that in certain positions if a player castles the board 
arrary can never be restored by valid chess moves to any position that existed 
prior to the castling. However unlike pawn moves and captures, the 
irreversibility is not necessarily the case after every instance of castling.

Whatever we like ....

Tom Volet
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.pairlist.net/pipermail/retros/attachments/20070104/f0f6ded1/attachment.htm>