All I can say is: disgraceful. I had no preconceptions about Parelli and in fact have looked at their website with interest a few times. But having watched the video, the only way to describe it is abuse.
Next time I see them advertising at Olympia (or whichever other horsey event they...
I don't think they're necessarily right for all horses, but my youngster goes far better in his than he did in a metal snaffle. I think they're more comfortable for a horse still learning about contact.