I think there is some confusion in this thread.
To some folks, "PvP viability" means being competitive against a random bad rogue wearing greens and S1 epics and hitting you from the front. That we can do already, and to an extent I agree that we may be able to fare even better in such situations in WotLK.
To other folks, "PvP viability" means being competitive against a reasonably good PvP player with appropriate spec and playstyle. In my opinion, we still won't be able to be competitive if we have to go deep in prot. There is no PvP gear to support deep prot playstyle either. By going deep in prot one loses either damage scaling or spell power scaling with gear.
By the way, folks should try dueling a good rogue - it's a nice "back to earth" moment - they stun/bleed/kite you to death, and there is nothing you can do about this. Bad rogues and warriors are the ones killing themselves against Holy Shield.
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