Have you used the new prot warrior spec for boosting yet? It's amazing!

They have a retribution aura-like talent so mobs take 20% of your block value in damage when they hit you.
Thunderclap hits for a crap load.
You can AoE stun the mobs in front of you, which does about 1000 damage.

Basically, spamming thunderclap along the aoe stun and you can clear the entire place in 1 pull. Run up to the boss, pull him and run back down the waterfall to the starting hallway and kill everything there. It's awesome!