Sometimes I see a defensive move in a problem that seems to save the position. But I know there must be a refutation, since the problems are computer generated. Wouldn't it be great if we could be able to check these moves online against a chess engine (say Crafty)?
henkvj, note that if you have a silver or gold membership, you can easily cut and paste the PGN or FEN notation into your own chess engine in a few seconds, and then try your defensive move. You don't have to set up the position piece by piece, which takes a long time.