Haha... One of my lesson horses had a bulldozing bone jarring trot and canter, he was an old Thoroughbred with all straight angles as far as I can remember. Excellent lesson horse, he was bombproof, never sped up or gave any mischief besides wanting to go ahead of other horses in group sessions. My trainer told me has one of the best athletic canters (I don't think I ever got the chance to ride him when my stiffness faded, but I did get a glimpse some times).
I would fall off that sucker like a booger, I would just get bounced so hard my whole body locked up and I would slide off to the side. I looked ridiculous coming off.
I would really have to relax, roll my shoulders back, and "find my seat" as my trainer would tell me tirelessly. The gelding had the tendency to sleep through the lesson or be a little lazy, I dreaded the idea of making him go faster but it did help waking him up and getting him moving more, so that his stride covered more ground and it wasn't just bang, bang, bang every time his hoof landed. He's a workman's horse... and tbh, I never really liked him much compared to the mares I rode. I liked the bratty Welsh greenbroke more than him x)