Personally I think he is a superb athlete who has a major problem: He cannot throw the football. Not a problem for a running back or tight end, but a disaster for a QB!
Even if you correct his horrible mechanics, he still has great difficulty reading defenses, which is why is completion percentage is abysmal. He throws wide of receivers to avoid any chance of interceptions.
He is a great guy, who is a true leader, but needs to accept that he would be better off at another position, or he will go down in history as being a nothing more than a marketing gimmick.
Think Elway thought he had died and gone to Heaven when Peyton Manning became available, and then chose the Broncos?

As a Pat's fan, I am ecstatic that the Jets signed Tebow. This should be the final nail in Sanchez's already shaky self-confidence.