Iv'e seen comments in other places about Chip Kelly being confident in his system and can just plug in the right QB.
Last year, with a depleted offensive line, Nick Foles lead the eagles to a 6-2 record as their starter before breaking his collar bone just as they got their starting center, Jason Kelce, back. They got their starting left guard, Evan Mathis back the next game. Their starting right tackle, Lane Johnson missed the first four games.
For the final 8 games, all three of those lineman plus all pro left tackle Jason Peters played. They did have a backup right guard.
Sanchez, the guy Chip signed to play in his system, went 4-4 in hat stretch, causing them to miss the playoffs.
Foles lead the Eagles to come from behind wins in the first 3 games of the season.
He lead them to within a yard of a comeback in their first loss to SF. A game where Riley Cooper dropped a perfect Foles pass in the end zone.
Foles also brought the Eagles from behind to take the lead against the Cardinals with two minutes left to play before their defense gave up the winning 75 yard touchdown. Even still, Foles lead them back to the Cardinals 16 and had a couple of shots at a game winning TD, with one ball being caught just out of bounds in the end zone.
That's how close they were to starting 8-0 under Foles.
And that is what people are calling a so-so year for Foles.
In 2013 he was a pro bowler with one of the best QB ratings ever.
Foles went 14-4 under Kelly in two years. He has a great arm for the deep ball and reads over the defense before each snap.
I think he could really develop into something special.
https://www.youtube.com/results?search_query=nick+foles