Trial flights
I can imagine that the odd Ops. Inspector, who's a control freak and would like to control everyone around, to have expressed to you such a wish. However i'm reasured that FCL 'Training Standards' have more nowse than that.
Not a perfect world but i'm sure that you would agree that bar the irritating exceptions, most of those that we take up for a Trial lesson want to do it for the actual hands on flying experience. I have known the odd chap who initially said that they didn't want to take control. And then, following the flight have enjoyed it so much that they have then come back and started a course.
So who saids where the line is drawn. How much flying is done must be between the Instructor and the student. That cannot be decided by law, thank God!