I've noticed something similar to this.
I don;t know anything about their abilities but I assume they have CDs like every other tank job, yet I have not seen a one use them.
An example of this was when I was doing my first run of Stone Vigil as a AST earlier today. The DRK died a total of 7 times, more than I have ever seen anyone die ever out side of raids. At first I thought it was because I was getting use to how AST works, and how it heals, but by the third time I knew it wasn't me. I was throwing everything I had at him, once I even did a string "combo" of Bole -> Benefic -> Enhanced Benefic II -> Essential Dignity -> Aspected Benefic and he STILL died to the mob of three enemies. The first boss killed him in three hits and me and the two Mechinists fought it without him because he returned to the start. I ran out of MP 3 times and I was using Luminiferous Aether every chance I had. It was messy, and the worst run of Stone Vigil I think I ever had.
Edit: I didn't even DPS. This is the first run I have ever done where I couldn't even throw out an Aero.
