lol, I think you just provided my point. The 13th data point was needed. Why do you think the Big 12 is adding a championship game? Not because they wanted to but because they were told they need a 13th data point (or as you say one more chance to beat a quality opponent).
No, I didn't prove your point. You are saying just having 13 games is the factor. It's who you play in the 13th game that matters. If your 13th game is against Louisiana Tech or somebody like that, the 13th data point does you no good.
The issue with Ohio St vs Penn St in 2016 is that Penn St had two losses. Ohio St not only had better metrics, they also had fewer losses. In 2014, Ohio St and TCU each only had one loss. For some reason, you and some other people can't get it through your heads that 2014 and 2016 were not the same situation, because Penn St had more losses in 2016. It's not an apples-to-apples comparison.