I saw this thread yesterday, right before I had to go to work. So forgive me for going back and commenting on an "old" post, lol.
Originally Posted by Alwaysbehind
All I know is I am not sure I would take advice from anyone who kneels down next to their horse in a tutorial video.
It may have not been a great decision to do in a tutorial video, but it shows the trust he has in his horse. Also you can see that the horse is standing without being tied to anything, so he has respect and trust from the horse. Even though the horse resisted, the horse did not fight against it, so the horse was willing to do what was asked. Granted I wouldn't be doing it in such a confined space like he is.
To the OP: Correct me if I'm wrong, but you are asking if this method would work in laying the horse down? Yes, but I would not do this with a green horse that you have not built up trust between you and the horse.
I have done something similar to that method with my horses. I don't see a problem with doing it, to teach the horse to lay down. If you do choose to do it, be prepared for the horse to resist and fight doing it, especially if you don't have the horses trust.