I decided to learn to do this too because of all that bad experiences, I've read, and I guess I'm somewhat of a control freak. I think explaining what you want is harder than doing it your-self. You can explain and leave pictures, and they say, "yes, I understand", but then they do something completely different.
To be fair, a few groomers have written in and said that in the first grooming experience you won't see a lot of change, because they try to make that as pleasant as possible; for if the first one goes well they usually aren't afraid after that. As a behaviorist you can probably see the validly of that statement.
