I shall add to the speed confusion. When I was a kid, I rode a good cowhorse who's origins were the YP ranch in Montana. When riding cattle all day no one wants a trot horse. A regular walk was just a little too slow so a single-footing horse became very desirable. Prince had a beautiful slow single-foot gait that gently rocked the rider side to side. He wasn't slow, about like a fast walk which worked well on a cattle drive. These horses learned not to waste an ounce of energy. I soon discovered that falling asleep was one of the pitfalls of riding one of these horses.