WHEN I USE THE WORD "TWIST", I AM NOT REFERRING TO THE WAIST OF THE SADDLE. I AM REFERRING TO THE TREE, AND HOW IT FOLLOWS THE SHAPE OF THE HORSE'S BACK.

There is an exercise I do where I place my palms flat on the horse's back, where the panels of the saddle would lie. I learned this from watching a Gaited Horse Clinician named Larry Whitesell. Click HERE for a link to a video that he does on his DVD set. Larry does not know me and I am not affiliated with Larry at all. I did buy his DVD set. You can buy his DVD Clinic at this link:
http://www.whitesellgaitedhorsemanship.com/sales.html
My left hand is AT the withers, where the front of the saddle tree would be. (DON'T PUT YOUR LEFT HAND ON THE WITHERS) My right hand is toward the loins, where the back of the saddle tree would be. (DON'T PUT YOUR RIGHT HAND ON THE SPINE) Hands are about 12 inches apart. If both hands are on the same plane, then the horse needs a "gaited tree." If the left hand is at a steeper angle than the right hand, the horse needs a "trotting horse" tree...like a quarter horse tree. These saddles have a "twist" in the tree that follows the back of the "trotting" horse. Click here to see pictures of our gaited trees.
Call me if you need help. Here is a video of me doing the exercise: On the right is a picture of where to put your hands.

Tony