In his 1986 Baseball Abstract, Bill James summed up one of his most important recurring analytical themes: "Bad organizations will tend to project their weaknesses onto their best players, and ultimately will dwell not on what the player can do, but on what he can't."
That theme also applies to pro football, and the most recent egregious case of this would have to be Kyle Orton.
During his three seasons (2005-2008) with the Chicago Bears, Orton posted a 21-12 record. On most teams, having a 26-year-old quarterback (Orton's age during the 2008 season) capable of winning two out of every three starts would be seen as a boon, but that wasn't the case with the Bears.
Orton's next stop was with the Denver Broncos. Denver actually fielded fairly strong quarterback play in the 12 seasons after John Elway retired (Brian Griese and Jake Plummer both made the Pro Bowl during their Broncos tenure), but in the end the team and its fan base seemingly won't accept anything less than year-in, year-out Elway-caliber play from its passers. This is probably why Denver has reportedly been considering trading Orton, and likely would have made the move if not for the lockout.
At this point, whether the Broncos end up keeping Orton or are able to send him to another organization is somewhat irrelevant. What's significant is the lack of willingness of two different teams to stick with him as the starter -- making many believe that Orton is a stopgap measure at best. There is also a perception in some circles that he might not be as good as some of the other potential quarterback acquisitions this offseason (either free agents or trade candidates).
The metrics make a clear case as to why both of those assertions are incorrect.