Quote Originally Posted by Lucy_Pyre View Post
No, the reason a 900 potency attack from, say, a melee DPS and a tank hit for different amounts is because Strength scaling for tanks is only around 2/3 what it is for melee DPS (or any other DPS and their respective mainstat). This is why a 1,200 potency Confiteor from Paladin will hit for significantly less damage than a 1,200 potency Midare Setsugekka from a Samurai despite both abilities having identical potencies.
And that scaling is due to the tank mastery trait. Tank Mastery affects both Vit and STR of tanks, while providing a constant 20% DR. Because of this trait, tanks have a slightly different damage formula to everyone else. I seen it some where recently in a forum post comparing the different formulae.