Crap. I really hate defending them, but those numbers don't tell me anything useful. They could easily explain it as "good halftime adjustments". Harbaugh started in 2015, and they always averaged scoring more than their opponents. And in 2016, probably their best season pre-covid, they had their best scoring margin after halftime. So those numbers tell me that Harbaugh was better than pre-Harbaugh. I don't think that's any surprise to anyone, though.
But, something happens that is different for pre-covid and post-covid. It isn't evidence of anything illegal, though, but should be analyzed. Did his brother slap him and explain how football works? Did he get an assistant who helped him learn to make second half adjustments? Did he suddenly create something innovative at *ichigan? I mean, I 100% believe he was cheating... that THEY were cheating. But if I just crawled out from under a rock for the first time in 8 years this morning, these numbers wouldn't convince me.