hmm..something i personally lack and think is pretty much REQUIRED to have good d is to have lateral quickness, and relatively fast reactions.

and just with that having the nose in line with their belly button thing. people say to me to stay low and have your legs spread out when playing defense. i do this, and man my friend just pro hops over me =_= something i find annoying, coz if i dont stay low he finds his way around me too =p