Of course I haven't.. its quite simple.
I agree with you, yes pancakes relies on the offensive system you run, yes. The more run heavy the more pancakes.
But it scales. to say pancakes are 100% playcall is nonsense. Since both pure pass blockers and pure run blockers both pancake, and technique blockers pancake just as well (if not better) than power blockers, there is no argument saying that a good blocker doesn't pancake, because a well built blocker will cake whether you want them to or not.
If you compare all the teams with the similar playtypes you can make an avg. number of pancakes for each play style, the very heavy run teams, commonly 4k+ rushing yards and <2k passing yards range in pancakes anywhere from ~650 to ~1350ish, the first number being pretty bad and the second number being elite.
http://glb2.warriorgeneral.com/game/compare_teams/278/87You can do the same thing with the heavy passers... commonly 4k+ pass yards <1k rush yards,
the range of cakes on these teams goes from about ~160 to ~350, the first number being pretty bad and the second number being elite.
http://glb2.warriorgeneral.com/game/compare_teams/32/75