I have a question for all you, since I'm really not a ranking expert on the wow number crunching. Question is simple, I know defense constitutes an added avoidance but does it work the other way around as well?
Does gear that give dodge, grant a small bonus of defense?
It just came to me when I doned an amulet from naxx 10, that had less defense than my old one, and it should have dropped my def below the cap. But it didn't and the only other stat on the amulet was dodge.
fast anwser: dodge gives no defense (rating or skill)
What I think happened is that you mistook the defense rating on your items for the defense skill you see on your character tooltip.
Note that defense rating is not the same as defense skill. The magical 540 number you need to be uncritteable in raids is derived from loads of defense rating. But let me put it simpler; about 5 defense rating is the equivalent of 1 defense skill that you see on the character tooltip