Who said this? I've never in my life heard this. It's about Improvement trends and averages. You are confusing consistently improving with consistently better.
Every coach has a plateau point with each team and we don't know where Kalani's is with BYU yet. But to suggest that Bronco is suddenly going to make BYU's coaches look amateurish in 1 game is... well; just dumb. The numbers and trends just don't bear that out and even if UVA or BYU wins handily it's still only 1 game.

So, I think the canard may be in your brain.