Monk IS the worst aoe DPS in the game. Death blossom and katon destroy monks AoE potential. Between the melee DRG>NIN>MNK in terms of AoE potential. As for trick attack, if you are looking at it on main targets, yes it adds something like 2.5% (correct me if I'm wrong, read similar numbers somewhere) raid dps over the course of the entire fight. But for add portions of the fight, trick attack makes things explode.
