How many keepers have you watched and thought, 'He's really improved - he must have a great coach'? Personally, I'm struggling to think of any in recent times. I don't mean just settling down after a period of acclimatisation to an unfamiliar league, or benefiting naturally from greater experience, I mean actual technical progress.
Genuinely, I've grown sceptical of what goalkeeping coaches actually can do other than the basics. Has Joe Hart improved? He's been criticised for his 'sweeping skills' and distribution since he became first choice for City and England and several coaches at club and international level seem to have failed to improve that aspect of his game. Guardiola didn't seem to think he could be coached, he just bombed him out of the club and brought in a keeper whose own flaws have been evident throughout his career.
Look at Rob Green - an ex-England keeper, but his concentration, decision-making and performance levels in general have always been poor - and he never, ever, seemed to improve, He's still making howlers now in a lower division. Would Grobbelaar blame Clemence, his England coach, for that? He was sitting next to him at the game yesterday, maybe he had a word.
It's entirely natural and understandable that if a keeper keeps making certain kinds of mistakes then people will point the finger at his coach, but without any real knowledge of what actually happens on the training pitch. If there ARE genuinely effective goalkeeping coaches out there, they must be worth their weight in gold, but I'm coming to the conclusion that the role is dubious in coaching terms.