The thing is, it doesn't actually matter what you, I or even the coaching team think of the use of a sports psychologist, its about whether the players find it beneficial or not. Clearly some do, Steve Peters work with British cycling is a classic example. Some players will have a lucky sock or a lucky way of getting changed, or they have a religion that they feel helps them. These are all mental aids to performing at the highest level they can, have a psychologist is just another one of those aids.
From the article it sounds like the use of a sports psychologist at Wasps is not new (Umaga said he used a psychologist last season to get him over a very bad patch & that, additionally, he had found god with the help of JTA!) so the better question to ask is if he's been there a while, it clearly isn't working so how good is he?