My coworker tests all her clients. I have always thought of it as cheating. I know for a fact she's passed two (or more) dogs just to get tem out of our office. Sucks and demeans the validity of the title.
Our trainer tests a lot of the dogs she trains. I got Gavroche tested before we ever took a class there, he never even met her before (we actually never took any classes at that point, did it all on my own). I got Logan tested two weeks after I brought him home, and again he never met her before. I prefer it that way. If the dog is used to the dogs around it and the people around it, what's the point of even testing? Most any dog can pass with familiar dogs/people/environment.