His record is actually very good (admittedly not at the Blades, having re-read your post). He got Leicester Promoted to the Premiership, got Fulham and Brighton promoted from League One, and Port Vale were top of the league when he joined us. If Speed had stayed and we'd gone down and sacked him last week, I couldn't think of anyone better placed than MA to manage us in League One, he has good knowledge of the lower leagues, knows what it takes to get out of them, and on top of that has now had 4 months to see exactly which players need to be got rid of and which youngsters are ripe to bring on.
Stability is whats needed and to sack him would set us back further, and it would take the new manager until Christmas to get to know these players, when we know now which ones aren't cutting the mustard.