On the one hand, I could see him being a good coach as he's a fairly 'nice' guy and if he was given a set of instructions, he would try to follow them to the book. I.e. "do this, then that for 30 minutes". Obviously, he is far too rigid in his ways for management which requires adjustments.
Anyway, on the other hand I think it may be a load of rubbish. Football is still an old boys club, and even if you're completely thick and stupid, you can walk into some pretty decent jobs. A lot of football pundits seem to say it as they're friends with him and don't want to offend him. He is also bad at handling all different types of players, and outs some, so I can't see him being good with that side of things.