we down 500 resil 12k hp priest under 5 seconds even after he pop pain suppression before anyone even touches him (after the first round of wtfowned, people tend to get paranoid when they face the same team, lol), or even SL/SL locks thats almost 500 resil with 14-16k hp.
and just as some may've guessed it, yes our 5v5 do have tri-melee setup. its a tad bit gimp but it works just as intended - gibbing clothies that cannot get away via immunes/blinks and what not.
my ap with tri melee is around 2.5k with 42% crit, warrior is around 2.7k ap with 40% crit, feral druid is at 4k ap with 47% crit. and all 3 of us in full pvp gear.
how much can a priest without PS take?
granted, tri melee does have a lot of weaknesses. but we still got other random compositions/setups to play with, so not really worried

bottom line, if ur even serious about pvp as a priest, 41 disc, with pain suppression is a must, not even debatable. save yourself, or your allies. and thats what a healing priest do, saving lives (yourself included, dead priests does nothing)