Gaited horse saddles have shorter skirts than other kinds of saddles to allow far more liberty of motion during the hip region. From 1902 the Universal Army Saddle was produced with a set tree, broad panels to unfold the load, and to begin with a front arch in 3 dimensions. https://zanderzpetb.wikiexcerpt.com/3856329/a_secret_weapon_for_horse_saddle_cover