ORIGINAL: ameyam
Low rates -50%. Set it, fly it. Best, let him see what he is comfortable with and standby him when he is flying to catch his mistakes.
DenverJayhawk, I myself did not try out dual rates till I went to my second airplane. But it is not a good idea to set full rates for a trainee. Some airplanes are too reactive: you dont want him to doink it into the ground even without trying a loop. I saw this problem when I moved to a Tiger and very soon set dual rates. Its OK on a trainer to set full rates though
Ameyam
I'm pretty close to this comment. The manufacturer probably specifies a high and a low rate. I'd set the plane up for the recommended throws and add about 20% expo then fly it yourself first. Then decide if he even needs high and low rates. You may wind up setting them both to the same rate somewhere in between the recommended high/low. It depends on the plane and the pilot.