Two can play that game...
Last year, ndsu beat ysu by 3, and then won a natty.
This year, they beat ysu by 21 at home, in a year that ysu makes the title game and ndsu does not.
What's the situation there then? Is ndsu trending up or down???
I don't disagree (no reasonable person would) that NDSU is not at the level they were, but your reasoning is pretty dumb.