We'll have to disagree again.
You're already seeing defenses step up with new schemes to counter the spread and pro style. Everything new becomes old, and what was once old will become new again.
Here's where your logic loses its luster.
Team Scoring Defense:
#1 - Clemson - 11.5 points allowed per game
#10 - Wisconsin - 16.1
#25 - Buffalo - 21.6
#50 - Rice - 25.9
We're not going to build a top 10 defense at Purdue, based solely on being able to get the recruits. So let's say we focus on a top 25 defense. Buffalo gave up 22 points per game. The 50th best defense (Rice) only gave up 4 points per game more. So with your logic, we would spend most of our recruiting efforts building a top10 to top 25 scoring defense, which are going to give up between 16 and 22 points per game, on average.
Top Scoring Offenses
#1 - LSU - 48.9 points per game
#10 - Louisiana - 38.8
#25 - Auburn - 34.0
#50 - Boston College - 30.9
So my question is, why wouldn't we focus on having somewhere between a top 25 and top 50 scoring defense, that gives up between 22 and 26 points per game? And then have a top 25 offense that scores 34 or more points a game?
BTW, here are the scoring offense and defense rankings for the 4 teams in the playoffs this year.
LSU - Offense #1, Defense #28
Clemson - Offense #4, Defense #1
Ohio State - Offense #3, Defense #4
Oklahoma - Offense #6, Defense #62
What do each of these teams have in common? They are all in the top 6 in scoring offense. What do they not have in common? Only 2 of the teams have top 25 defenses. And one of them plays in a crappy ACC conference, which clearly inflates their defensive rankings.
So you can see your argument of defense over offense holds no water.