What riding discipline uses what is commonly called a Cutback Saddle?

The only discipline that uses a cutback saddle is saddleseat. Saddlebreds, Arabians, Morgans, National Show Horses, and Tennessee Walkers are the most common Saddleseat breeds. Saddleseat pleasure horses pick up their feet really high and have very long tails. Saddlebreds were the original breed that saddleseat riding was performed on. But a cutback saddle is longer than a huntseat saddle, and it doesn't have knee rolls.