While sifting through some data, I realized the Eagles have unique tendencies on opposing sides of the ball.
Through three games, the Eagles have used the least amount of unique offensive lineup combinations with only 19. For context, the next closest teams are the Packers (26), Bills (27), and Bears (27). Then compare that number to the Seattle Seahawks who have used the most unique offensive lineups: 83. Big difference.
57.07% of the Eagles offensive plays feature their most common lineup, which is more than any other team. The next closest is the Buffalo Bills with 32.70%.
The Eagles are also the only NFL team to use the same starting lineup on offense for each game. Luckily for the Eagles, they haven't had many injuries, especially on offense. That certainly effects this number.
Chip Kelly is known for being an offensive genius, but he doesn't work his magic by using an inordinate amount of lineups, or at least so far. The Eagles use a lot of 11 personnel, meaning plays with 1 RB, 1 TE, and 3 WR. Not only does Chip use this formation often, but he hasn't been frequently rotating the personnel. LeSean McCoy (RB), Brent Celek (TE), and the trio of DeSean Jackson/Riley Cooper/Jason Avant have dominated the majority of offensive snaps.
It remains to be seen if this changes in the future, especially waiting to see if players like Zach Ertz, James Casey, and Damaris Johnson are worked into the offense more often. It's definitely something to keep an eye on. Mark Saltveit discussed a similar subject in his article entitled "Chip Kelly's Boring, Conventional Eagles Offense".
On defense, it's an entirely different story. Philadelphia uses the 7th most unique lineup combinations. However, their most common lineup is only used 11.40% of the time, which is 14th least.
The Eagles have only used 2 different starting lineups on defense. Again, though, this is due to injury. It would likely be only 1 if Bradley Fletcher didn't miss the Chargers game.
What does this tell us? Defensive coordinator Bill Davis likes to be creative in terms of lineup combinations. He's not shy to vary personnel There's more of a rotation going on in the defense.
By default, there seems to be a tendency of more unique defensive lineups than offensive lineups for most teams. I just found the extremes on different sides of the ball for the Eagles to be interesting.
With a difficult opponent, the Denver Broncos, coming up this week, I wonder if the Eagles will shift their tendencies on offense. I don't think it's likely, but again it's something to watch going forward.