They will pretty much both proc at the start of the fight. All this talk makes me really upset my Pally is Horde. Rabble rabble rabble! Lol.
I've run int a couple human engineer Ret's that have literally just wiped the floor with us as Ret/Disc. Granted, I play Ret/Spriest at the moment, and it is unbalanced 2's, but a good cleanse, fear ward, and trinket can keep him pretty well out of CC's for his CD's and he tears me apart faster than I tear him apart.