Thanks, Tom.

I think picks were less important back then for a few reasons. First, as Adam mentioned below, they did tend to come further downfield. Second, the offense’s ability to move the ball wasn’t as great as it is today, meaning that turning the ball over back then was less likely to result in an opponent scoring. The data used to derive the 45 yard interception penalty in THGOF came from the 80s, which was a more offense-oriented decade than the 70s, or even the 90s, really.

When Brian Burke did a study a few years ago, he used more recent data and concluded that, at least on first downs, a 60 yard penalty is more appropriate. The bigger penalty is fitting for modern offenses because the original 45 yards penalty (and the new 60 yard one) is based on expected points; these days, you cede more expected points when you turn the ball over, both by losing your own and giving them to your opponent.

I don’t have the play by play to do an expected points analysis for the 70s or earlier, but I think it is reasonable to assume that, given the harsher offensive environment back then, the EP swing from a turnover would be much lower and result in a concomitant decrease in the interception penalty. This is just a theory; I could be wrong (I often am).

I don’t know if there’s an equilibrium, but Rodgers seems to have found it.