Yeah the Steelers need him more than he needs the Steelers. Injuries are the only thing holding him back. In '11 he still had about 10 sacks, made the ProBowl and he missed all those games after breaking his face against the Texans. I think he got bad advice last offseason forgoing surgery until TC and that held him back last year. If he gets healthy, there is no reason to think he wont be that 10-15 sack type of guy he's been since '08. And yes, he is VERY under rated as a run defender too!
Harrison is still a damn BEAST vs the run no doubt.....But at his age and with the money he is due to receive then it will be hard for the Steelers to keep him....Its a shame but it is a business......I agree if healthy he could easily post double digit sacks again but that is a big.....IF