It was right to get rid of Hecky. In fact it should have been much earlier; he should have been shown the door after the Fulham away game.
And any normal club would have binned Wilder off too, way before the end of that season as in many ways it got worse. Probably after the Arsenal humiliation when we'd conceded 21 goals during 4 consecutive home games.
There is no changing things around without risk. I think back, for example, to when Ipswich got rid of Mick McCarthy and we had the usual "be careful what you wish for" warnings from the punditry wankerati. Sure enough, Ipswich did get relegated and spent 3 seasons in the 3rd Division but they're in a far better place now. I wonder where they'd be if they still had McCarthy boring them to death?
Of course, we had a similar experience ourselves. The trouble is there's still a hell of a lot of Blades who think that can be repeated.