And many rookie QBs start off being very bad at said progression and just stare a guy down and chuck it. Duh.
Many rookies also come from passing offenses or pro-style attacks. Tebow didn't come from that. He came from a shotgun spread team that ran the ball a lot, which is currently the new version of the option. It's the best offense for running the ball right now as it spreads the field out and kicks defensive players out to the perimeter. It allows RBs and running QBs running lanes that they wouldn't otherwise have in more traditional option/running offenses. So just his college background is a knock against him.
If it's a "rookie" thing then he's got to overcome that. Many rookie QBs never end up doing this too. The NFL QB position is probably the toughest position in all of sports.
However, if one is to be successful in this league one needs to learn to understand defenses and follow a progression, no matter what the age or experience is.
I'm not sure that he can or will do that. It's real tough to change old habits.
He certainly didn't demonstrate to me that he could, even at the college level. Some of you act like his bad throwing mechanics are the only knocks against him. His ability to read defenses is horrid. He no longer doesn't have the best and fastest talent around him anymore. And at this level, he won't be a one show pony able to run all over the place out of the shotgun spread.
Pocket passers who manipulate defenses and follow their progressions win in the NFL (Brett Farve, Mannings, Brees, Rivers, Brady, Aikman, Montana, etc) . These "hybrid" running and passing QBs (Alex Smith, Vince Young, Mike Vick, etc) haven't been very successful nor will they ever be with the athletic defenses the NFL has.
I'll be very surprised if Tebow is ever more than a backup QB in this league. Great college player, but just not cut out for the League.