I'm against using high speed video for players to learn when they are beginners. I think beginners need a good real live coach and after they can hit a decent fh bh serve etc. Then start breaking down the small details of pro strokes analysing video. A beginner needs less stuff in their head. But you need a good coach that shows the player the proper feel of the strokes. The body needs muscle memory and the brain just gets in the way when you have no idea what its supposed to feel like.
Or they can hit on their own and use their intelligence. Seen many juniors by now who never took a lesson from a coach but were only coached by their 3.5 fathers, who are now in college with a tennis scholarship.