I have an issue with most proposed warrior stat priorities.
This is a hit/expertise theory thread. Now... this thread will have almost no theorycrafting, this is more of a thought experiment. Feel free to discuss and call me wrong but... I have an issue with people saying mastery > hit/expertise. Now while I haven't done any raids so I don't know if damage is just meaningless or something, but if the assumption is you want to keep 100% shield block uptime, then I think the arguments for mastery over hit/expertise have the same flaws in arguments of people who in WotLK said, "go with avoidance because it's better to not get hit than EHP." Those people were wrong because over time, which is what all of the simulations so far are based on, the statistics break down and you eventually have a bad streak where you just flat out get hit. This is where healers get stressed and mana starts to become an issue.
So what happens when your theoretical over time RPS is high enough to average to always having SBlock up, but you aren't going for hit/expertise. You might have enough mastery (and avoidance) to theoretically hit that maximum, but what happens when you just flat out MISS with shield block or revenge? You take a full hit to the face, maybe even two.
Am I just talking out my ass here? But it seems like hit/expertise > mastery > everything else (with stamina still trying to decide if it's before or after mastery). Lots of people are saying go Mastery > Hit/Expertise or even putting Hit/Expertise on the bottom. I just have to strongly disagree with this.
I also disagree because I feel like excess RPS isn't a problem, here's how I see warrior playstyle:
Keep Sblock up, if for some reason you know you don't need rage use HS, otherwise bank want rage you can and use shield barrier as an "Oh Shit" button. As your current health value decreases, blocking becomes of lesser value, and absorbing can be better (obviously depending health amount and how hard you are getting hit), but at low values your healer is going to want you to absorb the damage to give them more time than block part of it because sometimes even if it's blocked it means a death and you'd rather absorb once and let Sblock fall than take even a blocked hit. Secondary OH shit button being Last Stand.
I feel like this is the best of both worlds between what Theckk calls the "bleed" strategy and the "high-TDR" strategy. It's damage smoothing + high TDR to an extent, and I feel like his "taunt switching" calculations aren't really what we care about. Okay, you're a tank, you're going to tank something for 30 seconds, if you can't survive that, especially starting with full rage, just freakin' reroll your character. The more LIKELY scenario to kill a tank is low health, low rage, and you HAVE to instantaneously generate rage, we'll call it "burst rage", and I feel like you don't need to do any math to say "well obviously hit/expertise is the best."
So the way I see stat priority is Hit/Expertise > Mastery (>= Stam??) > Avoidance. I feel like the math and general simulation philosophy in the discussion so far isn't representative of real tanking scenarios.
Anyways, that's my "tanking philosophy" thus far. Maybe I've just had too much caffeine and it's too late, but this seems reasonable to me. Please feel free to prove me wrong, especially if you're someone having great success in raids presently and know better what incoming damage looks like.