I don't think Sanchez "carried" the jets to AFC championship games... that jets defense, and run game is what carried the jets.. Sanchez never had a season over 56% completions (in an offense where they threw a bunch of short passes) and had 68 TD with 69 INTs.. You could have plugged a lot of quarterbacks into that team and the jets would have been just as good or better.
Yes the eagles offense is better than what the jets had and their run game similarly is a big piece of their offense like NYJ's was with sanchez, but I am not buying that sanchez is going to "carry" a team... Kelly is a smart dude though, so this will be another great measure of his coaching ability..
and sure their defense is underrated, but they have also played the offenses that rank 29, 21, 25, 27, and 24 in yards per play.