So, I go to the Devon Horse show every year (if you're familiar with it) not riding just watching. One time I was looking at the horses warming up and a lot of them had chains from front leg to front leg. I assumed it was for dressage, and it made them walk the way they do for dressage. Is this true? If so why do trainers use these and some do not? How do dressage trainers that don't use these chain things get the horse to walk, trot, canter the way a dressage horse does?