We can watch a game and see all kinds of errors that will cause a team to lose a game. Dropped passes. Missed tackles. Bad snaps. Missed kicks. Etc. Things that do not relate in any direct way to coaching unless you feel players are being coached to commit those errors.
Personally I'd rather have a coach be honest and reference the things we can all see rather than make some trite statement that its all the coach's fault.
Now things like roster management, game planning, team motivation..those are coach issues and I appreciate a coach recognizing that. Fuente certainly does.
So if it makes you feel good to know everything is the head coaches fault then Coach D is your man. Personally I'll take being real and respecting a fans intelligence like Coach Fu