But being dynamic isn't necessarily what an NFL franchise wants from its starting quarterback. It's fine if he is, but it's more important that he's dependable -- that he'll show up on time (and Manziel has already arrived late to a preseason meeting) and do what he's supposed to do and comport himself in a way that enhances the team around him.
I'm not sure Manziel is capable of attending to such details. Assuming he starts for Cleveland (and I can't imagine he won't), he'll almost certainly offer double his share of Highlight Moments, much to the delight of ESPN, to whom he has become the New Tebow. But I'm not sure he'll win. I'm not sure he'll make the routine plays that an NFL quarterback must. I'm not sure his temperament will allow him to be just another quarterback, as opposed to being the famous Johnny Football.
And now you're asking: But don't you like his fire? His zest for the game? His will to win? I do. But everybody in the NFL wants to win, and everybody tries hard. In professional football, it's the details that matter. It's not enough to make the occasional big play -- if it were, Tebow wouldn't be a full-time employee of the SEC Network -- at the expense of a half-dozen middle-size plays. I'm not sure Manziel understands that. I'm not sure he'll ever understand it.
Because he was essentially able to call his own tune at A&M -- remember that ridiculous suspension of a half against Rice? -- he has never had to grasp that doing whatever he wants whenever he chooses can have consequences. He's Johnny Football! ESPN loves his act! The Worldwide Leader can't get enough of him!
Here's the thing, though: What ESPN creates, it can also destroy. Teams eventually tire of seeing themselves depicted as the supporting cast for Tebow or T.O. or Ochocinco. (The exception is LeBron, who's good enough to make any team delight in being his supporting cast.) It will take a while -- the Browns won't give up on Manziel just because he flipped off the Redskins -- but eventually his NFL team will decide that Johnny Football is more trouble than he's worth.
That's provided he keeps trying to be Johnny Football and not simply Johnny Manziel. If he can control his excesses and play to his strengths, he can be a good NFL quarterback. If he can't, he'll soon be sitting next to Tebow -- whose failing wasn't excess but the lack of an NFL skill set -- in a studio in Charlotte.