This is in response to the video, not the OP question.
What makes bitless so much "kinder" than bitted? I personally would rather see the rider keep constant contact with a mild snaffle than a hackamore with leverage.
While that is a fairly mild hackamore, I kind of had to cringe to see it ridden with so much contact. To me it looked like the horse's head was in a vice, because it had NO relief to the constant rein pressure. I like hackamores. I like bits. But, generally speaking, I try not to ride with constant, solid contact. It kind of makes me cringe when people do that.
Yes, there are times when you have to pull more than you want to, like when the horse isn't in control. But that wasn't the case with the dressage horse in the video. To me he looked like his head was in a vice with no relief in sight. It did not look like soft contact to me. But that is just my opinion.