I agree with you Old. His tackling ability was poor, at least the few times I've seen him try to tackle. I would think that by now, any LB knows you usually can't arm tackle RBs. He seemed to try, and fail, at that often.
OTOH, I bet he has a lot of good stats as far as being in on tackles.
I don't know enough about what is really expected from the two ILBs in a 3-4 to argue strongly on this. I brought this point up a while ago and some other fans disagreed strongly. They seemed to have good reasons.
All in all, I see him as a weak ILB or run stuffer.