AP top 20 9 of 10 times. They were top 10 in 5 of 10 times. This was in spite of them going 1-9 vs. Notre Dame. I'm sure you'll concede it's easier to get a higher ranking with a win vs. ND than a loss. It is very hard to imagine that Kelly would have gone 5-5 playing teams of that caliber.
Holtz also played 30 teams that finished in the final AP top 25 in his first 5 years, 19 of those teams earned those rankings despite a loss to ND. Not sure of Kelly's exact numbers but they're both decidedly lower.