[alberto_ol]

When I was in high schhol I won a game in a tornament because I hoped thet my opponent didn't know the rule. Otherwise it would have been a draw.

[vasco]

Also had that happen in a school tournamen when I was young! Nowadays, over the board I try to force it in a first game with a new person to see if they know it and if they don't take my piece, I'll bring it up to prevent it being a problem later :)