Looks like defensive stats might be better at predicting Super Bowl scores than regular season scores. Hopefully this reinforces the idea that a strong defense is a strong offense, and shows how that giving an inch can indeed result in losing a mile.
I've been sitting on this one for a looong time, because I got sidetracked trying to figure out how to use the R tool to generate residual plots (we were on an older version at the time, that didn't appear to include them). I finally figured out how to do it, even though they're part of the standard linear regression tool output now! I took the Intro to Advanced Analytics training at Inspire 2019, and we asked about residual plots. The instructor advised us to calculate the residuals and create the plots ourselves, so I'm guessing this is a pretty recent addition.