In terms of raw numbers of guys to the NFL from Iowa and from Iowa State, you are correct. But the same program/mindset that allows Iowa to punch above its recruiting weight also makes it possible for a motivated opponent to stay close/win. Most of Iowa's NFL talent is at OL, TE, DL (with some DB and LB mixed in). While impressive, the lack of offensive skill position NFL talent is glaring. Iowa hasn't traditionally been able to just out-athlete Iowa State by having a QB turn nothing into something, or a RB just dominate with his talent (Beathard last year and Greene in 2008 were exceptions).
It doesn't excuse some of the perplexing losses that have happened in the series. My point is that Iowa's talent isn't such that it can just roll out and win like an OSU.