That is impressive, even for a glacial era of offense. I read somewhere 1977 was the rock-bottom year for scoring, in terms of points per game. Thus all your rule changes in 1978. But could it also not be that the late '70s marked maybe the greatest era in team defense in NFL history? You had a lot of memorable defenses playing together then, even historic flashes in the pan like the Falcons' Grits Blitz defense.
Just to throw this off the rails even more, but I have never felt throwing the ball 70 times a game means you will score more. The 1972-1977 Steelers, with a maturing Terry Bradshaw, averaged 23.7 ppg. In the first eight years of Ben Roethlisberger playing for the Steelers, they have scored 22.8 ppg. The Patriots are averaging 29.0 ppg over the last eight years.
Nobody really plays old-school ball control anymore. You'd be hard-pressed to come up with one memorable defensive unit since the rules were changed in 2004.
thanks devil. those are interesting numbers. as a side note, the raiders averaged 25.3 points that season.