Chris Brown nails it with this post. Particularly this:
… Designing an offense is all about structure. Constraint plays, like the bubble, work when the defense gives you the play by their structure; same for play-action passes over the top. When I say these are defensive cheats, I mean they aren’t the base, whiteboard defenses you expect, because defenses — both players and coaches — adjust to take away what you do well. But you want to go to your core stuff, so you build your offense off of that, and each constraint play forces the defense back in line, right where you want them. That’s the beauty of football: punch, counterpunch.
Successful play calling isn’t about keeping the offense balanced. It’s about keeping the defense off-balance with the plays you call.