Mark Crossfield has been a PGA professional for a long time now, he has given lessons to a wide range of clients. Something he really respects and values during the lessons he takes is when the pupil questions his methods and reasons as to why he is getting the pupil to do certain movements in his swing.
Through questioning Mark the pupil will get a far great understanding of the golf swing and what Mark is trying to do to improve them. He would strongly recommend you do this with your coach.