A saddle sitting with its pommel lower than the cantle is not in the correct position — and everything that follows from that position is compromised from the first step.
Forward saddle tilt is most commonly caused by a tree too wide for the horse, the saddle positioned too far back, or uphill conformation. The result is a rider whose weight tips forward, loading the horse's forehand and restricting front-end movement.
Tree too wide: When the tree is wider than the horse's back, the pommel drops because the bars have sunk below their correct position. Most common cause, creates simultaneous lateral instability and forward tilt.
Saddle too far back: A saddle placed behind its correct position will often tip forward as it seeks its natural balance point. The correct position places the front bars 2–3 finger-widths behind the back edge of the shoulder blade.
Uphill conformation: Horses built higher at the withers than the hip create a natural forward slope that encourages the pommel to sit lower. May require a saddle built to compensate for the horse's topline angle.
A rider in a forward-tipping saddle has weight tipped toward the pommel, driving it onto the horse's forehand. This produces a shortened front stride, reluctance to lift through the shoulder, and a tendency to stumble. In reining, this produces poor lead changes and difficulty in the small slow circle where engagement is required.
David Solum has been evaluating saddle fit problems for 40+ years. Call, text, or email him directly — he can advise on whether it's a fit issue, a tree problem, or a saddle you should replace.
See also: Free Saddle Tools · How to Fit a Western Saddle · Parts of a Western Saddle · How to Buy a Certified Used Saddle