Yesterday is one of my favorite posts — with just one picture, you can see why NFL teams have become more pass-heavy over the last 70 years. It is not debatable that the NFL is more pass-happy now than it used to be: teams really are throwing more often than ever before.
However, what is debatable is whether or not the increase in quantity makes passing more important than ever before. The correlation between ANY/A and winning percentage doesn’t show that passing matters more now than it did in the ’70s. This is because passing efficiency is more compressed now than it used to be, which arguably makes having a great quarterback less important now than ever before.
Lest you think that claim is crazy, note that the starting quarterback for every Super Bowl champion in the ’70s is now in the Hall of Fame: Johnny Unitas (with a hat tip to Earl Morrall), Roger Staubach, Bob Griese (with a hat tip to Earl Morrall), Griese, Terry Bradshaw, Bradshaw, Ken Stabler, Staubach, Bradshaw, and Bradshaw. Heck, 6 of the 10 losing quarterbacks in those games are Hall of Famers: Fran Tarkenton three times, Staubach twice, and Griese, with Craig Morton appearing twice, too.
The graph below shows the standard deviation among all teams in Adjusted Net Yards per Attempt (the single best measure of passing efficiency) for each team since the merger. As you can see, the variance is declining, which means the best passing teams aren’t standing out quite as far from average as they used to:
There’s a reason for this, I think. And that reason is the switch to the short-area, low-risk/high-completion percentage passing attack has taken over the NFL. This lowers the ceiling for great passing teams and raises the floor for bad passing teams: if more and more teams are leaning on safe, simple throws, that both masks bad quarterback play and limits great quarterback play.
Take a look at the standard deviation among NFL teams in completion percentage:
The 2009 season stood out as the last big year for variance, for both ANY/A and completion percentage. Perhaps not coincidentally, that season saw the MVP (Peyton Manning) and the ANY/A leader (Drew Brees) face off in the Super Bowl. The 2015 season stands out in the other direction: the league was remarkably compressed in both ANY/A and completion percentage. And, again perhaps not coincidentally, that season saw the last-ranked QB in ANY/A (Manning!) defeat the 6th-ranked QB in ANY/A (Cam Newton) in the Super Bowl.
So what’s the takeaway? Yes, teams are passing more than ever, but teams are also throwing safer and easier passes than ever. And, I would presume is an uncontroversial statement, safer, easier passes require less skill from passers than riskier and harder passes. And those two factors seem to balance each other out when it comes to making great quarterback play more or less important than ever.