Copied from the same thread in the general forum:
I have quite a bit of admittedly self instructed experience in hypnosis and such things, so I'll chime in.
The arm tugging is a pattern interrupt as used in the handshake situations. In this country, the US for me, it is customary to want to shake someone's hand when they offer theirs. When you then do something outside the realm of what they expect, like tug their arm hard, it interrupts the expected pattern of behavior.
This ideally creates a moment of "what do I do now, I've never been in this situation before" within the subject, thus opening them up to suggestion quickly. Ideally.
The yanking of the arm does seem overly violent in the video, but keep in mind that when someone you don't know well thinks you have the ability to hypnotize them, and they are open to hypnosis, this opens the door to a trance state much more easily than walking up to someone completely at random and yanking their arm.
Looking at the backgrounds in the video, it's likely they were hired at some event and the people attending expected hypnotists to be there. Thus, before the hypnotist walked up to them, they were more likely than your average stranger to expect to be hypnotized.
Regarding the price, it should be that high for several reasons: first, if you think it's too high, this product would be a waste of your money anyway. Second, this is not a fly by night technique, it's a method for accomplishing something that really should only be in the hands of professionals.
Judging by how quickly product is expected in the online magic forums (and I include this site), this product wouldn't suit 99% of the people posting here.
Pj