Winning 1 league title with the amount Mancini has spent should not make him untouchable. While he won the league, he got eliminated 2 times in a row in the CL group stages. Same with the FA cup last season.
Good season in the League last season. But hardly a miracle with the squad he had....but awful in the rest of the competitions (expect the carling cup). This season he did even worse in the CL (how he has managed that i never know)....and is doing worse in the league as well. People have every right to question whether he is the man to take City forward from here.
But tbf, he couldn't have done much better in the 2010/2011 season. That was a great season.