I've been reading through this thread (well, skimming the last couple of pages, I admit), but... Hasn't anyone mentioned the stronger Protect that WHM has? That protects against magic damage instead of just physical? And the fact that most, afaik, endgame damage is magic damage?
The stronger Protect and Stoneskin was the main reason I hurried to level up WHM even though I prefer SCH; to have better buffs in 4-man stuff, where I couldn't depend on a fellow healer to do that for me :p