Can you imagine one of the best quarterbacks of all time serving as a backup? Oh, you can't? Yeah, me neither.
There are some players that are meant to be backups, and there are some players that are meant to be starters.
Brett Favre is not a backup player.
Who even said he's even interested in playing backup to Vick? It's obviously implied that he would be Vick's backup, but would he really want to? I think not.
Just like many of the star players in sports today, Favre has an ego. He's a top-five quarterback on any list and he knows that. It's his ego that won't left him retire, and it's his ego that will not let him play backup to any quarterback—no matter how good he is.
Between teams such as the Washington Redskins, the Miami Dolphins and the Seattle Seahawks that have potential gaping holes at the QB position, I don't see why Favre would want to play backup for the Eagles.
The Eagles clearly have their starting quarterback in Vick, who just came off a phenomenal season. Favre could serve as a mentor to Vick, and help his game in certain areas, but then he's better off as a QB coach than a player.
Favre has too many question marks with his health and injuries and for championship contending team to take a risk on him. How much money would he want? How many years? How much of that is guaranteed? What if Vick gets injured and Favre steps in and performs well? Do you sit Vick and start Favre?
I'm sorry, but if I'm a coach or GM, that's one too many questions for me.