>Warriors would see the smallest effect save for above classes,

I'm not sure this is the case -- in practice, warriors more than any other class farm out the shield/aura potions, stoneskin, etc.

Personally when I play a warrior I'm lucky to have even as much as stoneskin up for a fight, but if you look at who actually gets this stuff it's mostly warriors.

Maybe that's in part because warrior is such a populous class.