Clearly you don't know the PA38 very well it IS a very good trainer! But due to spar life & lack of new parts it is not an economicly viable aircraft for training.
A & C, I would not go as far as to say he does not know the Pa38 very well - read the other posts and the Pa38 seems to split instructors pretty much down the middle - I DO know the Pa38 well, have a lot of experience in a variety of trainers and am firmly in the "Its a poor trainer" camp, though I do think it has some good points, from an Instructor point of view I would rather not have any of the Piper/Cessna family, but if I was setting up a school that had to put dinner on the table I would probably go down that road