A common question is: what kind of offense do you run? Often someone – both fans and coaches – respond and say: I run a system with bubble screens, play action passes, screens, and draws. This person – coach or not – would be completely wrong. These kinds of plays are not your offense; your offense consists of the zone-read, the dropback passes, or your base runs and passes. Those other plays are sort-of conditions precedent to your offense; they work as constraints on the defense. What do I mean by this?
At least in the most abstract sense, your “offense” is that bread and butter stuff you can draw on the whiteboard that should always work in a perfect world. It is the pass play that always works against Cover 3, it is the run that will always burst free against a “Bear” front. Yes, it is what works on paper. But we don’t live in a perfect world, right? Well the “constraint” plays are designed to make sure you live in one that is as close as possible.
For example, the safety might get tired of watching you break big gains up the middle, so he begins to cheat up. Now you go play action and make him pay for his impatience. The outside linebackers may cheat in for the same reason. You throw the bubble screen and the bootlegs to make them pay for their impatience. The defensive ends begin rushing hard upfield; you trap, draw, and screen them to make them pay for getting out of position. If that defensive end played honest your tackle could block him; if he flies upfield he cannot. So you have to do these “constraint plays” to keep them in check. Once they get back to playing honest football, you, in essence, go back to the whiteboard and beat them with your bread and butter.
Now, in a given game your offense might look like it is all “constraint” plays: all gimmicks, screens, traps, draws, fakes and the like. Maybe so. If the defense plays too aggressively, so what. But a coach must not lose sight of how his offense is truly structured. A great offense is structured around a core idea or a few core ideas that puts the players in position to succeed every time. The triple option can be this for some teams, a well designed dropback pass game for another. The constraints are alternatively given too much and not enough weight. But they nevertheless are what make an offense go.
So the better you are at dropback passing, the more you need these constraint plays because teams will go out of their way to prevent you from chucking it all over them. Similarly if you’re a great run team. Safeties and linebackers will all cheat by formation and post-snap effort to stop your run game. You must have the counters, the screens, the bootlegs, and the quick passes (because quick 3-step passes, at core, are most effective when used to simply take advantage of a loose defensive structure). All this comports well with a game theory approach to football. Similarly, these constraint plays will be even more important against the best teams because they will put the biggest premium on stopping your primary threat.
The upshot of all this is that when you are designing an offense you must (a) find those one or two things which you can hang your hat on and beat just about anything doing when the defense is playing honest, and (b) get good at all those little “constraint” plays which keep the defense playing honest. You won’t win championships simply throwing the bubble screen, but the bubble will help keep you from losing games when the defense wants to crash your run game. Same with draws and screens if you’re a passing team. You find ways to do what you want and put your players in position to win and score.
ADDENDUM: Fair question from the comments: Does the theory work in the other direction? What if your offense is based only on bubble screens and then you just run the ball or throw the ball as a counter to your bubble screen offense?
Response: The difference is that the bubble screen is a play that really only works when the defense has made a structural choice or is out of position. Most commonly, you'll run when the bubble only when the defense has but two defenders to cover three receivers. You thus block the two defenders and the receiver has free yards. If the defense puts a third defender there they can take the play away, intercept it, or make the tackle.
Conversely, a well designed dropback pass play, a triple option play, or certain base runs will work every time you face a normal defense. The only time the play stops working is when certain defenders cheat on their assignments, either by alignment or aggressiveness.
Here's how they fit together: You're an option team. You come out running the option, you read the defensive end and the linebacker, and you tear them up. Now the safety or outside linebacker cheats in. He blows up your play. But, voila, now they are not covering your outside receivers, so you bubble screen them.
Similarly with a play action pass. You send a receiver deep down the middle or the seam. If the safety plays honest he should drop back and take it away. But if he comes up for your run play you use his aggressiveness against him.
The distinction is subtle, but important. It relates to the idea of base plays and counter plays. The bubble is simply not a base play. It will not work against a simple and sound defense, but works great against defenses that aren't structurally sound or balanced. On the other hand, "base plays" defeat balanced "whiteboard" like defenses, but can get blown up by defenses that cheat or play games. Thus the relationship between "base plays" and "constraint" plays (or "keep-em-honest plays). The bubble, while limited in use, will have a profound influence when the defense gets out of position.