Garry Neville once wrote that United would rather sack all players than a manger(cant remeberthe exact wording). In my opinion the 6 year contract was signed to show the big egos in the dressig room who the main man is.
Im sure that some/most players werent convinced Moyes was the right man. I think thats part of the reason of underperforming United. Players dont want to die for Moyes....
So the 6 year conctract is a message to players. Accept Moyes or die.
Having said.that...,im sure its.not as easy...there.must be some conditions or gentelmans agreement to terminate it.
Which again hasn't worked. And I doubt that the club has finances to replace all the players, at best they can do is to buy Everton and then get all their players in loan.
It was simply very bad management from the club. From letting both SAF and Gill to leave the club at the same time, to giving Moyes absolute power. The transition would have been handled much better if Gill was still there for another transfer window, the club would have chosen the assistant of Moyes (similar to have other clubs do), Moyes wouldn't have been let to dismantle the entire coaching staff and finally he would have been given a list of targets to choose from.
SAF did the things himself but he was SAF. Moyes was/is still the guy with zero experience on a top club so I don't know why the club thought that he will simply do a SAF. Letting him a bit constrained (until he proves himself) might have been better IMO.