[sblock="ooc"]Honestly though, one could argue a creature is not going to know you're in TD. Considering that TD isn't some sticker or badge on your forehead and given the fact you still have your weapon, and given the fact you can change your stance from round to round...i would argue it's meta-game for the DM to have the creatures realize that the players are in "Total Defense" unless the DM is going to provide players with that same type of meta-game information.
If you've ever watched a boxing match or a cage match fight, fighters will switch their tactics from moment to moment. None of them drop their guard and realize, "Oh, the other guy is in Total Defense mode and won't be able to AoO me if I try and grapple him or trip him." [/sblock]