I don't follow pro football too closely, but from what I see Tebow had so many strengths in college at Florida that Urban Meyer just let him play, winning a national championship, breaking some of Emmitt Smith's rushing records at Florida and Herschel Walker's rushing records in the SEC, winning a Heisman etc. It worked fine for Cam Newton at Auburn too - just let 'em off the leash.
Now he's in the NFL and everyone's bigger and faster than just a few people he ever played against in college, but - he's big & fast himself, he's large & durable, and he's really smart; and with Elway's help Tebow will know what he needs to learn. So with him and Newton, you've got got a guy with the size of a receiver, the strength of a running back, a good-to really-good arm (so far) and the smarts to learn how to be a great quarterback - barring injury, I'd say "hold on to your hat."
When you'd see Newton or Tebow drag four 250 lb. college lineman into the end zone with them, it was often because they just didn't expect it and couldn't believe it was happening, and that ain't gonna happen any more. But I wouldn't be surprised if the pair of them re-write the rules as to what's expected from a quarterback. One thing's for sure, and that is that high school "running backs" all over the country are working really hard at throwing footballs and trying out for their team's quarterback position, and just the number of them that will be coming up is going to change what's available to coaches.
Regarding Peyton Manning, he's through, and everything you've been watching about his "comeback" has just been maneuvering to try to secure some of the hundreds of millions of dollars at stake. They've been sly all along about exactly what they were doing to him, but just a few weeks back I read that he had been in for his third operation and they finally admitted they had to fuse 2 vertebrae. Though mine is degenerative rather than injury-started, I have had the exact same injury to my neck - the vertebrae tilted and began abrading the spinal cord underneath. And the instant, fast and only treatment is to fuse three vertebrae, C4, C5 and C6. And then you can't turn your head, and the "wrong" hit will paralyze you. So they fused only two, but it would still be suicidal to get out there and Peyton ain't that dumb. It's all just PR at this point, and hoping their (Andrew) Luck will change. You build a team around one brilliant player, and that player goes down, oh well.
