As a group, Cowboys fans are interesting creatures. There is a very vocal segment of the fanbase that cannot stand Jason Garrett's offensive philosophy; they believe it is stale, outdated, and that the league has figured it out. And what really infuriates the fans is the offense's tendency to run the play-clock all the way down before snapping the ball.
Yet there is an equally vocal segment of the fanbase that mocks Chip Kelly's offensive philosophy. They call it a gimmick, based on trickery, and say it is only a matter of time until the league figures it out. What really infuriates the fans is his offense's tendency to hurry up and snap the ball.
Neither of these is true. I have written about Garrett's offense here, and Coach Gary has done a great job highlighting what Chip Kelly does here, here, here, here, and here (Coach knows a lot about football!).
I don't want to rehash everything that's already been written, but a quick overview is in order. Jason Garrett and Scott Linehan, both run similar versions of the old Air Coryell system. There are a ton of variations of the Air Coryell, but the overall philosophy revolves around a strong running game and deep shots down the field. Coaches use motion to attempt to put their players in favorable matchups.
Chip Kelly on the other hand uses a hurry up spread offense (no he does not run a read-option. He will run read-option plays, but that is not the basis of his system). As the name implies, this offense is predicated on spreading the defense wide and getting offensive players in one-on-one matchups in space. Kelly also loves misdirection, getting the defense moving one way and having the play go another.
What's really interesting to me though, is the idea of pace, and how it is so different for both teams. Chip Kelly's Eagles lead the league in time between plays at just over 22 seconds. Dallas on the other hand is dead last, at around 29 seconds. Dallas meanwhile is ranked sixth in the league in time of possession while the Eagles are second to last. Clearly the teams have different ideas on the importance of pace.
Let's start with the Eagles. As mentioned, the Eagles attempt to pressure a defense by spreading it out wide. This puts a lot of pressure on each individual player; if they make a mistake in their assignment there are no players nearby to cover for them. The pace Chip Kelly plays at just adds to that mental pressure.
A quick exercise is in order. Imagine being given a test with 60 double-digit multiplication problems on it with an hour to finish. For most of us that wouldn't be a problem. Now cut your time to 45 minutes. Probably still not a problem, but you're going to be rushing some. 30 minutes? Eh, maybe a couple of mistakes because you're hurrying to make sure you finish. 15 minutes? Now the mental pressure is getting to you. It's a simple concept but a powerful one; the less time a person has to think and make a decision, the more often they will make a mistake.
That's the true nature of Chip Kelly's hurry up offense. Yes, it can tire out a defense (more on that later). Yes, it makes it hard to substitute, but as teams increasingly play nickel as their base this is becoming less important. But what really sets Kelly's hurry-up apart is the mental pressure it puts on the defense, which must recover from the previous play, diagnose the current one, remember their keys, and make the correct initial movement, all in 22 seconds. Easy enough to do it once. A little harder to do it 70 times.
So what are the Cowboys doing differently? As mentioned, a large part of the Air Coryell system is based on matchups; getting a particular player matched against a particular defender. The Eagles don't care about matchups, they care about spacing; all they need to do is line up correctly and the play is run. But when Tony Romo and company come to the line, Romo is examining the defense and looking for those matchups, like Dez Bryant on Bradley Fletcher. Romo also likes to have the play clock wind down as it forces the defense to show its intentions. You'll often see a man go into motion just to return to his previous spot. This forces the defense to react, and lets Romo know if the defense is in man or zone, allows him to spot blitzers, etc. Dallas also likes to substitute a lot, which also slows down the pace.
The main difference then is that where the Eagles offense attempts to force the defense to make mistakes, the Cowboys offense doesn't care what the defense does. It relies on offensive execution; if the play is read and run correctly it will be successful, no matter what the defense does.
We saw one of the main weaknesses of the Eagles' fast pace on Sunday night. If the offense can't get going it doesn't put pressure on the opposing defense, it puts pressure on its own defense. When playing a team like the Seahawks or Dallas, a team that can grind out drives and kill clock, the Eagles' fast-paced style of offense can really wear out its own defense.
It can also put a mental strain on its offense. We talked about how hard it is for a defense to read, diagnose, and react in that short period of time. That same strain is also on the offense, especially the QB. Players are forced to process a lot of information quickly. Role players that don't see a lot of playing time, new players forced in because of injury, or just players under a lot of stress will make mistakes on assignments in this offense.
There are two major problems with Dallas's pace as well. The first is that while it allows the offense time to read the defense, it also allows the defense time to set. There is no mental strain on the defense. They have time to set up, think over their keys etc. It literally becomes a battle of execution.
The second problem is the strain it puts on the offense. Dallas mitigates this somewhat with its big play ability, but in general teams that play at a slower pace have less scoring opportunities. The less scoring opportunities you have, the more efficient you have to be to score. You can afford to go three and out a few times if you're running 12 drives a game. If you're running seven? Not so much. Dallas's offense is based on execution, and it must execute every time.
Both offenses are attempting to pressure the defense; one through matchups the other through pace. Both have strengths and weaknesses. The main takeaway from this, and one that relates to every system in the NFL, is simple. There are no right or wrong systems. No system is going to be perfect, they all have their strengths and flaws. Some defensive systems match up better against certain offenses, some match up worse, and vice-versa. The worth of a system is based on the players that are utilizing it. To quote the philosopher, "that's all I've got to say about that".