Many people start natural horsemanship as they think it is a kinder way to train horses. Kinder than what is the question? Traditional horsemanship is based on negative reinforcement but often does not teach the correct use of negative reinforcement. So it may be that there is no relief from the aversive stimulus used to form a behaviour.
Natural horsemanship does teach that it is the relief from the aversive stimulus that reinforces the behaviour, so for those people happy to use aversive stimulus to train it may well be the better option. Unfortunately if this is all we have in our toolbox we will have to escalate at some point.
Natural horsemanship uses some very descriptive language and seems to be more horse friendly but is it any different?
No I personally don't think it is, it still uses negative reinforcement which escalates if the horse does not do as asked.
So we have the traditional people teaching back up by putting pressure on a headcollar or poking the horse in the chest and the NH people doing the same but calling it a game.
Of course horses respond very well to negative reinforcement because they do not wish to be poked or pushed or hit with a whip.
It is entirely up to a persons conscience to decide what amount of averisve stimulus to use or whether they wish to use positive reinforcement.
All we can do is tell them the facts - why negative reinforcement works. It works due to the fact that any animal will work to avoid aversIve stimuli because it doesn't feel good.