playBunny: castling significantly changed the method of attacking the king in the middle vs. the flank. Also, the lack of a 2-square escape move for the king resulted in more of a disadvantage for black. That's more akin to the cube. en passant, you're right, it's not much at all.
(hide) When moving in a game you can choose which one will show up next by selecting the appropriate option in the list next to the submit button. (pauloaguia) (show all tips)