I know about Hartwell, and I'm with you on Clark. I wish he'd play more but apparently Gibbs prefers the pass coverage skills of Simoneau over the run stuffing skills of Clark.
But with Abraham, ask most Jets fans (of which I am one) and they'll tell you, loads of talent, no heart, inconsistent, and always hurt.
If you get his A-game (which is rare) he'll dominate. But more often than not when he plays you get his C-game.