some spriests like to use trinkets that frontload a ton of damage, but it's not sustainable and over the course of a few minutes, is usually a dps loss
it's also very RNG based, spriests have the lowest crit % in pvp of any other dps, takes 5 gcds to get the 10% dmg buff and it's very gimmicky to put out a real burst
they've been fine, like all dot classes, when it comes to BG total damage, but now, with trinkets and the troll racial i can put out a mean 10 second burst, although you can easily dispel them all before they do 10k damage if you're certain classes