[81alum]

I feel like screaming this.

From a defense's point of view, there is no such thing as predictably advantageous play calling. 

As others point out, a defense must as well prepared to defend the less likely play than the more probable one.

RRP, PRR, RRR, PPR--it does not matter.

This argument, endlessly repeated by Stanford fans, drives me nuts.

But defensive coordinators put in different personnel packages and call different defensive alignments depending on what they expect the offense is most likely to do.  Sure, the players all have to be prepared for anything regardless of package, but stopping the run when you are in dime or stopping the pass if you are in short yardage puts you at a disadvantage.  If a team always runs on first down and always passes on 3rd down, then a DC can always put 9 in the box on first down and nickle or dime it on third.  And that makes a difference.  Perhaps I don't follow your meaning?

[81alum]

I feel like screaming this.

From a defense's point of view, there is no such thing as predictably advantageous play calling. 

As others point out, a defense must as well prepared to defend the less likely play than the more probable one.

RRP, PRR, RRR, PPR--it does not matter.

This argument, endlessly repeated by Stanford fans, drives me nuts.

But defensive coordinators put in different personnel packages and call different defensive alignments depending on what they expect the offense is most likely to do.  Sure, the players all have to be prepared for anything regardless of package, but stopping the run when you are in dime or stopping the pass if you are in short yardage puts you at a disadvantage.  If a team always runs on first down and always passes on 3rd down, then a DC can always put 9 in the box on first down and nickle or dime it on third.  And that makes a difference.  Perhaps I don't follow your meaning?