After some quick testing I have found that holy shield the talent that deals small damage upon successful block can apply gushing wounds. So by merely getting attacked (by spellcasters as well mind you, prot can block spells) you can proc gushing.
That’s all well and good, but the cool part is that retribution aura procs it as well. A 60 yard aura that returns insignificant damage when your allies are attacked by melee.
So the thinking of course is that in a BG, a prot pal with full gushing and ret aura will have the pressure of a shadow priest, assuming there’s plently of melee on the enemy team.
The question is if it’s worth it in arena to lose a second stack of divine steed for ret aura. Probably not. I don’t know the numbers behind gushing, if it has an internal cooldown or what, but perhaps against certain melee cleaves especially with dh, who has very fast attack speed, it could be worth. Either way pretty cool for bgs imo