Both are offensive masterminds, but even before the season begins, it's become very obvious that the Eagles offense in 2013 will be significantly different from last year's team.
After all, running back LeSean McCoy called the practices "a freaking track meet."
But although Kelly has definitely made the team significantly better from the disaster of 2012, he hasn't been perfect.
The following eight slides will highlight some good and some bad from Kelly's current tenure with the Eagles, in no particular order.
Michael Vick's regression in 2011 after his dominant 2010 season was fairly predictable, but no one in Philly could have seen what would happen in 2012.
Vick turned into one of the worst starting quarterbacks in the National Football League, throwing 10 interceptions and fumbling 11 times in 10 games. He did lead three dramatic fourth-quarter comebacks, but he missed time with a concussion and ended up losing his starting job.
Set to earn more than $16 million in 2013, Vick was a virtual lock to be cut during the offseason—or so it seemed.
But the Eagles restructured Vick's contract, giving the soon-to-be 33-year-old a one-year deal loaded with incentives.
They shouldn't have done that. Vick is in major regression. His struggles in 2012 can largely be blamed on the offensive line missing three starters, but he also hasn't shown the accuracy, intelligence and quick decision-making to lead the Eagles.
Kelly's offense requires all three of those. I would have made training camp an open competition between Nick Foles, Matt Barkley and Dennis Dixon.
But Vick shouldn't be on this team's roster. He's like the shiny toy in the store that breaks down a week after you start playing with it.
I don't see the Vick experiment ending well, and with his large contract, it's hard to envision him entering the season as a backup.
The impact of a particular NFL draft cannot be properly judged until three years have passed, but on paper, it appears that Kelly did a solid job with his first draft.
Offensive tackle Lane Johnson has the speed, strength and versatility to succeed in Kelly's offense. Tight end Zach Ertz will add a whole new dimension on offense. Defensive players Bennie Logan, Jordan Poyer, Earl Wolff and Joe Kruger figure to be impact players in a few years.
And, of course, quarterback Matt Barkley has a chance to become the quarterback of the future. If he doesn't pan out, though, it was only a fourth-round pick the Eagles used.
All in all, this looks to be the second straight very impressive draft by the Eagles.
A casual fan could have watched the Eagles over the past two seasons and realized that this team has some serious toughness issues on defense.
From Nnamdi Asomugha to Dominique Rodgers-Cromartie to Kurt Coleman, the Eagles defense has been soft, weak and not very intimidating.
Kelly attempted to change that this offseason, signing and drafting players who are notorious for their toughness, such as Cary Williams, Bradley Fletcher and Connor Barwin.
Nnamdi Asomugha, Dominique Rodgers-Cromartie, Nate Allen and Kurt Coleman were the four members of the starting secondary in 2012. None will be a starter in 2013. Points for Chip Kelly.
But he loses points for not replacing any of the four with an above-average player. From Cary Williams to Patrick Chung to Kenny Phillips to Bradley Fletcher, the Eagles' secondary is full of players with potential but not a lot of actual success.
Basically, no one really knows what to expect from them as a group this season.
They'll definitely be better than the 2012 group, but wouldn't it have made more sense to add a member of the secondary with a high or mid-round draft pick?
It's not just the fans who seem to have grown fond of Chip Kelly very quickly. The players really like him, too.
Center Jason Kelce has already said that Kelly is easier to talk to than former coach Andy Reid.
It remains to be seen, of course, how Kelly's style will translate on the field.
No one plays just one position on Chip Kelly's team. That would be boring and predictable and Kelly is definitely not boring and predictable.
There's James Casey, who plays fullback and tight end, but can also line up at wide receiver. There's DeSean Jackson, who will likely be lining up on the outside at wide receiver, but in the slot, at running back and possibly even at quarterback.
Even some of the offensive linemen will probably get in on the action. As a former college quarterback, Lane Johnson seems to be a prime candidate to catch some tackle-eligible short-yardage touchdown passes.
Chip Kelly might be getting a little bit carried away with the way he is attempting to use some of the players on the team.
Little-used tight end Clay Harbor will drop to the fourth tight end on this year's roster, but who expected him to be playing on the defensive side of the ball? He is, though, as Kelly has him working at pass-rushing linebacker.
The biggest surprise, however, is slot receiver Jason Avant working on the defensive side of the ball, in the secondary. Avant is known for his great hands, but not his speed. He was a perfect fit for Reid's West Coast offense, but he may be a surprise preseason roster cut in 2013, given Kelly's tendency to use tight ends over slot receivers.
For what it's worth, there's almost no way that a player like Avant, already 30 years old, could make any sort of impact at secondary.
The Eagles haven't gone public with the decision, but it's become obvious that the team is switching its defensive scheme to a variation of the 3-4 defense.
The switch helps players such as Brandon Graham, DeMeco Ryans, Connor Barwin and Mychal Kendricks, who all played in a 3-4 defense in college or in the NFL.
It also helps last year's first-round draft pick, Fletcher Cox, who can easily move from tackle to end.
Not all of the players are a fit for the new defense though. Veteran Trent Cole has never played in a 3-4 defense.
It remains to be seen how the team adjusts to defensive coordinator Billy Davis's new style of defense.