Not taking damage beats taking damage. Being able to heal beats not being able to heal. That's true regardless of class and gear.
using Backstab & Shiv beats standing at range and seeing the Boss Enrage over&over
when we did our first 55HM (that was Hammer station) we had only 61/63 gear (shadow [sin] tank, Scoundrel [OP] Healer, 2x commando[merc]) i could keep myself up just using the AOE HOT,
we wiped 3 times to the Enrage with our 4 try (this one a Kill) i had the knack out and could use both these abilities almost on CD while keeping myself and the Tank up.