I'm at work and dont have my materials handy, so please bear with me...
I believe priests have a tiny healing spell (only heals something like 1 wound with a recharge), but once out of combat they could, effectively, reset the party to no wounds? Or is there some limitation I missed on healing spells/near-infinite casts out of combat?
That seems to take a lot of the 'oomph' of combat out of any party with a healer.