I'm not all that interested in tanking, and I don't need to be perfectly geared for it, but here's what I intend to do.
DE all my tanking specific gear, with the exception of the Essence of Gossamer.
At this point, my dps gear, being heavily focused on agi and crit, gives me much better avoidance and absorbs anyway. I will be low on hp though, so I intend to get my frost resist out of the bank, resocket/enchant for stam exclusively and swap a number of them in my tanking gear to add loads of HP, depending on the situational needs.
Of course my tanking gear wasn't stellar to begin with, I'm raiding mainly as resto. I see a chance to reduce the clutter in my bags though, and I think I'll take it ;)