The Steel Curtain's secret

 

Consider the erosive effect of the Cold, Hard Football Facts when it comes to washing away the persistent belief of the "pundits" in the importance of the ground game.

 

You know the story by now: conventional wisdom tells us that the ground game is omnipotent. The Cold, Hard Football Facts inundate this belief as if it were a gridiron Galveston circa 1900:

 

The passing game, not the running game, is what really matters in pro football.

 

We've discovered more evidence of the importance of the passing game here in the choppy whitewater wake of Pittsburgh's victory in Super Bowl XLIII.

 

The 2008 champion Steelers fielded one of the best defenses in recent memory. This defensive success naturally drew comparisons to the great Steel Curtain defenses of the 1970s. We wrote about these comparisons ourselves during the season.

 

The conventional wisdom is that the 1970s Steel Curtain was a dominant defensive powerhouse because it stopped the run so effectively. Even our own pal Peter King at SportsIllustrated.com perpetuated this myth.

 

He recently wrote that stopping the run was the "hallmark" of the Steel Curtain.

 

King is a friend of the Cold, Hard Football Facts. He's been very good to us and has contacted us over the years about various stories, and we know that support from writers at SI.com is the reason why we have our nifty little relationship with them today.

 

But in this case King is incorrect, as are all the others who have perpetuated this fallacy over the years, to the point that the dominance of the Steel Curtain run defense has become unquestioned gridiron gospel.

 

The truth, however, is that the 1970s Steel Curtain was sometimes very good against the run, but sometimes not so hot. The Super Bowl champion 1975 Steelers, for example, ranked 22nd among 26 NFL teams, surrendering 4.23 YPA on the ground.

 

But here's the secret to the success of the Steel Curtain: It was always good against the pass. In fact, "good against the pass" does not do the Steel Curtain justice. The best way to put it is like this: 

 

 

Defensive Passer Rating, one of our Quality Stats, provides all the proof you need.

 

The 1973 Steelers, for example, featured the greatest shutdown pass defense of the Super Bowl Era, allowing quarterbacks that year a combined 33.1 passer rating.

 

How good is that? Consider that if every pass their opponents threw that year fell incomplete, they would have had a Defensive Passer Rating of 39.6.

 

The Steel Curtain was just getting warmed up in 1973: All five Pittsburgh defenses from 1973 to 1977 – a period which includes the franchise's first two championships – rank among the 20 best pass defenses of the Super Bowl Era.

 

The 1972 Steelers, meanwhile, the first team of the Steel Curtain dynasty, narrowly missed the Top 25, with a 47.0 Defensive Passer Rating. The Super Bowl champion 1978 and 1979 Steelers boasted Defensive Passer Ratings of 51.8 and 53.3, respectively. Those two teams led the AFC in Defensive Passer Rating each season and probably would have made our Top 25 list, if not for the rule changes before the 1978 season that launched the Live Ball Era and led to inflated passer ratings (more on Live Ball Era Defensive Passer Rating soon).

 

The numbers are awe-inspiring: from the dawn of the Pittsburgh dynasty in 1972 (the year of the franchise's first postseason victory) through its last title of the era in 1979, the cumulative Defensive Passer Rating of the Steel Curtain was about 45.0. You could argue that this is the most amazing statistical team accomplishment in NFL history.

 

The end of the Steel Curtain dynasty, meanwhile, coincided directly with a dramatic drop-off in the team's ability to play pass defense. The 9-7 Steelers of 1980 fielded a unit with a humble 67.7 Defensive Passer Rating. It was the team's worst performance against the pass since the 1-13 campaign in Chuck Noll's debut season of 1969 (75.0 Defensive Passer Rating).

 

Size up the Steel Curtain here:

The success of the Packers, as we've noted many times, was largely due to the success of its passing game. Bart Starr, the subject of a recent Cold, Hard Football Facts interview, was the greatest quarterback in NFL history.

 

But it takes more than the greatest quarterback in history to make one of the greatest dynasties in NFL history. It also takes a shut-down pass defense.

 

You'll notice that Green Bay's Super Bowl teams of 1966 and 1967 earn spots on the list above of the greatest pass defenses of the Super Bowl Era (No. 25 and No. 6, respectively).

 

Inquiring minds might want to know how the team's pre-Super Bowl champions of 1961, 1962 and 1965 stack up.

 

They stack up quite well, of course.

 

The 1961 Packers posted a Defensive Passer Rating of 53.7, second best in the NFL that year. The only team better was the Eastern Conference champion Giants who the Packers beat in the title game that year.

 

The 1962 Packers, easily the most dominant team of the Lombardi Dynasty, led the league with a 43.3 Defensive Passer Rating.

 

The 1965 Packers also led the league in Defensive Passer Rating, with a mark of 48.2, far and away the best in the league that year (the Redskins were second, with a 57.9 DPR).

 

Call us crazy, folks, but this looks like a trend.