Yeah I would agree that horses learn from release. I will say that video didn't look real good but I don't really want to judge it because it had stuff cut out and could just be showing the 'bad bits'.
Also I'm not sure this fits in but aren't you not supposed to put up videos/pics of people just to bad mouth them.
Watching this I can tell you that he IS releasing. If you watch his hands you will see he is tugging and releasing. If he were not the horse would not be mouthing the bit and would do much more head tossing. In fact, he is doing very little steday pull. There is a stop where he does this and the horse resists and then puts his head up and hollows his back.. at wwhich point the rider backs the horse some more.
He is also using a leading rein and separating his hands quite a lot which is common in training a horse that is green to what is being asked.
Personally I do not like all the backing. I know why he is doing it.. it is a common thing to do this to get the horse to learn to collect and shift his weight to the rear and this horse is doing that part of time.
He does release the horse. I would be more subtle with the tug and release.. I prefer to have a shorter rein and to squeeze and release with my hands.. sort of like squeezing a sponge. It is a softer request than what I am seeing here. I also think that if he sat up straighter it would help the horse.
I have seen MUCH MUCH worse than this video (in real life). It is more harsh than I would choose to be, but the horse does not look terribly uncomfortable of unhappy actually (and it does pay to read the horse). He is responding for the most part and is not yawing for the most part.. he is actually working the bit and doing quite well.
I believe the backing is excessive. Just my opinion.