Color me deeply, deeply skeptical.
To summarize, the problem for Tebow is that, because Florida placed so much stock in his running game, they never really developed some fundamental skills a quarterback has to have in the NFL, where being a rushing quarterback is not an option. Tebow took all his snaps from the shotgun, so his footwork on the 3/5 step drop is terrible.
And then there's that throwing motion.
Quarterbacks hold the ball at chest level after the snap. With most of them, when their man is open, they pull the ball back and up behind their ear, and from there go into their forward throwing motion. Tebow drops the ball down below his waistline and winds way back and up, doing a full 360 degree motion with his elbow. What that means is that Tebow holds onto the ball much longer than his peers and (supposedly) delivers a much lazier spiral. In a league where there's only a split second window where your man is open and you have to get him the ball in the blink of an eye, an elongated throwing motion can be a killer.
Of course, a similar critique was leveled at Vince Young, and it stopped him neither from getting drafted early in the first round nor from performing relatively well as an NFL quarterback (after some fits and starts, anyway). Admittedly, Tim Tebow is probably better than Young was. Maybe Tebow will come out of this training a fully formed NFL quarterback, but my guess is he's still a pretty major project for an ambitious coach with a healthy if aging franchise quarterback.