Unusual Conformation & Movement Question

I saw a QH the other day and he had bizarre conformation and movement. I was really curious as to whether the specific conformation caused the unusual movement.

The horse’s hind end looked completely non-correct. The hind legs were post-legged, they were literally stick-straight. Also, he always looked a bit camped out behind. Overall his hind end didn’t look underneath him, instead it was out behind him.

His movement at the trot felt very exaggerated, like you had to post super super slow to an exaggerated movement. It didn’t feel jarring, but just over-exaggerated.

Any ideas?

Was he halter bred, by any chance?

he wasn’t halter bred, he came from blue valentine, or something like that. I am conjecturing that since his hind legs were post-legged and camped out behind him, then he had to really thrust his hind legs forward for each trot step. or something like that?

I have a halter-bred stove-pipe legged gelding, and even with arthritis, his trot still feels like a normal 1-2, 1-2, 1-2 type trot.

The strange moving horse felt like "oooonnnne-twoooooo “ooooooone-twooooo”

Weird…