Peyton Manning or RGIII your choice

[biffle]

Originally Posted by Mahons21

Furthermore in my opinon, Manning's decline will be much less pronounced than other QBs, because his dominance stems more from his mental preparation more so than it does his physical attributes. Manning was never going to wow crowds with his athleticism, and while he can make all the throws in an NFL playbook, he doesn't have one of the strongest arms in the NFL. Manning wows the crowds because he knows what plays a defense is running better than they do. This is not a skill that is going to diminish over time, if Manning still has the arm-strength to complete every NFL throw, there's nothing to suggest he can't once again be one of the top franchise QBs in the NFL.

Or it could be that he has less he can afford to lose in physical skill, and less to gain in experience, which could make his decline steeper. In baseball, speed players lose their value less as they age than other players.

In fact, go look at the careers of the 10 QBs Pro Football Reference has as most similar to Manning. It's only the mobile ones- Young, Elway, Favre, Staubach- who didn't become shells of themselves after the age of 35. Montana, who was always reasonably, but not overly, athletic, was still good for a couple of years, but definitely off his peak year performances.
The other 5 on the list (Unitas, Marino, Anderson, Kelly, Fouts), who seem to all fit exactly the profile you laid out- not over athletic, not earth-shattering physical skills, but cerebral and prepared- all would have done well to retire by the age Manning is now.