I doubt he's worried about being Wally Pipped so much as trying to prove his toughness (which fans and media have erroneously questioned before) and play for his new contract whever that might be. My point is you have to assume he's not afraid of McCown taking his job, so he's not rushing to get back. His contract will be based on how he plays for the whole season, whether that is 14 starts or 15 it's really not that much of a difference, and it serves him no purpose to rush back and potentially play poorly due to lingering health issues. So, if he says he's healthy enough to play, and the doctors say he's healthy enough to play, and the coaches say he's healthy enough to play, he is healthy enough to play.