Actually although it may have originated and is more commonly used in the European countries, some Americans utilize it. I use it not for a whoa command, but a calming command. It does mimic the relaxation exhale that horses use and it brings my horses anxiety level down. When I'm doing ground work I also pair it with lowering my body when my Tb gets a bit anxious.

well as he said in the video he doesnt think that horse had ever really been rein backed before so the horse would be focusing on it at the point and the horse itself wasnt a refuser so he didnt have to worry too much but on a horse that does yeah sure for a few seconds it might but it can still see the jump the whole time so it knows that its not getting to go away from the jump and relieve that pressure. Personally i think as long as you dont let horse go past the jump and just turn it back around to immediately try again. Though the horse i ride is less a serial refuser and more a OMG IVE TOTALLY NOT SEEN THIS JUMP THIS HEIGHT BEFORE IN THE LAST TIME I RODE type even though he has. but after the first try he always jumps it lol

Place the horse I front of the jump walk him over it he can do it. Don't give him to much time to think about it or he will be like okay am I jumping I'm jumping oh no it's here I am not jumping that anymore, kicking him in front of the jump helps to.

I guess it's a comforting, pleasant noise to tell him he's being good.

Lots of people I know use it as a "steady" or positive aid

its telling them to whoa

hmm it was just weird as a have never seen that before... but i can understand how it would be like a click maybe? idk, it was just new

yea i tought it to my horse to tell her to stop

It's a calming sound.

No it's stitching