guys, every week someone comes up with a new "easy way to win NFL games" and posts it after it's already won 4-5 in a row. Once they post it goes to $hit otherwise you would know exactly what it is and how it did in the previous 12 weeks. Anyone who truly relies on stats and systems tests them over a number of weeks and knows exactly how it performed...
since we're guessing I'll say it has something to do with the differential b/w each team's yards per play...but just a guess
of course any system that deals with defense (assuming the D is defense and not differential) means GB is the play