It is a conclusion that just doesn't follow.

You ever heard of something called the Pygmalion effect? Did the study control for it?

By which I mean, did they control for the beliefs of the teachers who were training these subjects, in reference to:

• the trainability and potential of the subjects themselves, and

• the teachability of the subject matter itself?

For example, did they tell the teacher they had a bunch of students with superb hypnotic potential who just needed some encouragement to get going, or did they tell them they were conducting a test, to see who was trainable, or if it was possible to train hypnotic ability at all?

These things make a HUGE difference to whether people actually learn.