IIRC a similar thing happened in Italia '90 with Bobby Robson who changed the formation mid tournament after some of the players had it out with him. I don't think it is necessarily a bad thing if the players then take the responsibility they have demanded.
IDK about the tactical skills of Shearer but he certainly looked passionate about the England job on the TV last night. Of course that's not enough on it's own but 2 years and a tournament is long enough to find out if you have picked the right person. I wouldn't mind him being manager...
Of course it's down to the manager, no question. If players don't understand and believe in the the philosophy of the manager then they are doomed to fail. Mourinho is a good example of how this works, when his players go on the pitch they are fully focused and ready to kill. Great managers make...