I also think it isn't apples to apples because Weis actually was quite literally .500 his last year and had the 3-9 year.
I think the admin figured Weis was incapable of meeting their half assed objective of one above average year out of every five and being 8-5 ish the other years.
As I have said before, the problem with Kelly is he is an above average college coach. Good enough that he likely will not drop below the bar to losing seasons like the other failed ND coaches did. Thus, he likely won't get fired sans a really prolonged string of 4 or 5 loss seasons or by suddenly proving he sucks even worse via a losing year.