I think if one were to look at it with unbiased eyes, you have two realistic options:
1) The winning season was a fluke, a one off, a season where everything went right.
2) He built the program up to a winning season, and then promptly tore down what he built to attain 2 wins again.
This is really just semantics to me, but when somebody in sports uses the phrase “built up” they are almost never using one season as their evidence. At least I’ve never seen it. Building a program directly implies long lasting effects.
Regarding the other coaches there, while never having a winning season, his predecessor had 3 more wins the year prior, his successor had one more win the year after. They all had a similar overall win percentage, with Hauck having the lowest overall (27% vs 23% vs 33%). So statistically, pretty easy to say he did the worst, but they all did quite bad.