He's a bust for the Titans. When you use a Top 10 pick on a QB, you don't expect them to be gone by Year 5. Regardless of how well they played in those 5 years, if a team is giving up on a QB after 5 years, then he's technically a bust.
When you use that high a pick on a QB, you should be taking him with the assumption that this player is going to be our QB for the next 7-10 years, if not more. If you don't think that about the guy, then wait to the end of the 1st or 2nd round to draft him.
And this is the fatal flaw of drafting QBs. Teams have such a need at the position, they essentially take 2nd round talent at the top of the draft, and then are scratching their heads 3-5 years later when they are giving up on the likes of players like Rex Grossman, JaMarcus Russell, Matt Leinart, Vince Young, etc.
Now Vince Young has won a lot of football games (over 60% of his starts) and is a good, effective QB. But he's fatally flawed. He's at that crossroads in his career now, where he could go by the wayside or he could actually make enough improvements to his game where he can prove Jeff Fisher wrong about him.
True...and yet a guy like Jamaal Anderson or Deangelo get a different evaluation though the money may be the same and, frankly, they may produce more in terms of quantifiable stuff sooner than many QBs who may hold a clipboard a couple of years. Then, there are guys like Jason Campbell. Bust?