I disagree that Brown and Stoops took over under the same situations, but I am not going to sit here and argue other football programs with you.
I don't consider the BCS or bowls to be the ultimate goal to judge a new coach by, just as I do not consider records to be that way. Each year, the team needs to keep improving, especially in the places where it is currently weak. The recruits needs to be high caliber and need to usually pan out to be as good as they are hyped to be (this is a sign of a good recruiter, when your recruits actually do pan out to be as good as you expect...can't always happen, but it should be the common theme).
Exceptions happen, of course, when you lose most of a great unit at the end of the year and their replacements take over. You can't always improve, but the setback from the replacements shouldn't be huge and they should continue to show promise of greatness.
If these things continue to happen, you will see Nebraska continue to improve overall and return to being a contender. So far, under Callahan, they have continued to happen each year. Watch the secondary this year...they will be far better than last year's, and that's something we needed to have happen.
The wins come with these things. The above is what really matters...the wins are secondary. Merely a result that gets too much focus during the rebuilding.