Could be. I know that if she perhaps has some lines from the Nez Pierce horses, they had a gait called the "Indian Shuffle" some foundation Appys have that gait today. (I know she looks nothing like a Appaloosa, but it was just a theory considering she is a wild horse.)
Poor thin little mare. I can't help but feel sorry for the horses crammed in pens and often looking worse off than they were in the wild. Some people say the BLM is good, and some bad. But it's pretty hard to recreate a picture of a herd of wild horses starving to death in a pen. I've seen plenty of pictures of the praries they graze and by no means are they small and over-grazed.
But off that topic~