They probably scissor cut it to make the horse look groomed. For show it would be ~pulled~ short and thinned, rather than just cut, much shorter, and banded to make it lay flat and completely still. Hunters and dressage riders will do the same thing. The idea is to show off the neck. All the western quarter horse and thoroughbred/warmblood types show this way, except in rodeo, where specific turnout isn't a part of the tradition.
Arabs and types like them, Morgans, National Show Horse, etc show with long manes.... but the bridle path is trimmed down a lot further, at least 12 inches, removing what is often the thickest bushiest part of the mane and better showing off the neck.
Jenny just called, she is coming to ride in the morning too, with Heather and I, so I may ride Trash. I'll see how he does in the arena first.
Becky