Re: stam/mastery. Now that I've actually tanked some stuff, I'd say stam is better, but obviously you can't reforge stam and I would still use stam/mastery hybrid gems in yellows and go for mastery socket bonuses. I'd say stam edges out mastery, but not to the extent it did in WotLK where you just went balls deep into stam. The reason that I think stam edges out mastery is because sooooo many fights and mechanics can't be blocked and sblock will cover any damage smoothing you need.
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