He isn't infallible in footballing terms by any means. He makes mistakes and he's the first to know when he's made a mistake. He is infallible however in terms of his leadership, character and integrity. I'd sooner go down with him in charge, get bought out in the summer and kick on from there than replacing him now with some run-of-the-mill mug on a short term appointment that keeps us up.
Also, we needed a squad in the summer and 45M is nothing these days when you need to bring 6 or 7 in. I'm sure he was promised more money anyway and never got it (keeper, striker, 10).
I think people are still reeling from the Kinnear/Pardew/Carver/McLaren debacle, and to have a man of his stature leading the club is some kind of elixir on healing wounds, especially that he's pretty much the only positive selling point we have at the moment.