I guess the thing to keep in mind is that Warrior tanks are going to basically have two modes, switching based on whether the fight has significant unblockable damage or not. Block fights will obviously prefer Mastery, while for Barrier fights, Mastery will do very little. The interesting consistency between these two builds is the lower value of pure avoidance stats; Parry and Dodge have a lower value in a Block fight due to rage income being important for keeping Shield Block up, and in a Barrier fight they are almost as poor as Mastery.
So I suppose what this all means is that progression tanks will have a lot of on-the-fly reforging to do. For me, though, I’ll switch out what I can, probably mainly trinkets, but reforging between fights is a bit beyond my commitment level.
As long as I’m talking about gear, it’s also a bit of a shame so much of the current tier is so poorly-statted [so much Dodge >_>], but I guess it gives them somewhere to go in the next tier. I know they know how to do it well, because I noticed they did it with the “Masterwork Spiritguard” entry-level crafted tank set. You should see that thing… Mastery on literally every slot. Beautiful.