I think you are being too harsh on him. lol I think he makes less that 20% bad decisions. The only time he had bad decisions was when we had a pen full of s***** pitchers. there wasn't a right decision to be made. once the team got rid of a few problems and brought in better relievers there wasn't a problem.
the better the team, the less the manager matters and as you say, any monkey could manage the team we have now and not f*** it up.
anyone can squeeze milk from a cow's tit, but you can't squeeze diamonds out a goats ass.