There’s also the fact that the distribution of ratings isn’t uniform, i.e., the difference between 1 and 10 is always much more than between 151 and 160. So even a straight average of what is the #108 team (Oklahoma, at 102.8) and the #3 team (Texas Tech, at 90.0) would put you at 96.4, which would rank #20.
Bottom line, if you start from a mediocre place and start playing defense at a top-10 level, you’re going to shoot up the rankings regardless of any recency effect.