To be fair, I'm not convinced goalkeeping coaches are that important. I admit I say this from the position of someone who has barely any reliable understanding of keepers. But I wonder how much good professional keepers are reliant on specialist coaches to improve, rather than on the accumulated common sense of the keepers' profession and their own ambition and drive.
In Reina's case, for example, I suspect he scapegoated Achterberg as his own pride in his own performance declined. Reina put on weight - he surely didn't need a coach to tell him this was wrong - and his general attitude began to stink. For a keeper at his level, at a club of LFC's stature, he surely should have been pretty much self-sufficient by that stage, and, to be fair to Achterberg, I doubt the coach deserved to be blamed for Reina letting his standards slip.
Outfield coaches have seen outfield players' standards decline, with weight and attitude problems, and they've not been pilloried for their failure to change such players. Some players can't be helped. Much.
The basics of the keeping coach's job - taking the player through video analysis of his own performances and those of opposition attackers, identifying weaknesses and working on training sessions to improve certain areas while maintaining strengths - are surely pretty much standard and straightforward by now. I expect, and hope, that certain little refinements can be added by those coaches with the sharpest eye for details, but I'm not convinced that most keepers will dramatically improve or decline depending on who is coaching them at this stage in their careers. Maybe I'm wrong, but I'm sceptical that Mignolet's weaknesses are more down to Achterberg than himself and his own disposition, brain and natural physical instincts.
From what I hear about Achterberg he's assiduously thorough on all of the technical and analytical business that goalkeeping coaches do these days. Outsiders with no access to all the stats and video material that he has can see what Ming's problems are, so I can't believe Achterberg isn't working on all those issues.
So maybe a coach with more passion, more of a motivational personality, is out there - and of course I'd be all for any improvement we can get - but maybe we just...well...need to buy a better keeper?
I've moaned about coaches in the past, but I'm not convinced by my own arguments now. I feel now that you either get a keeper whose overall game is already sound, or you suffer with one whose game is flawed. But it probably doesn't matter who is coaching them.
That's not to claim I know what I'm talking about, but I've lost a bit of faith in the idea that there'll be any improvement if Achterberg is replaced.