Text from the extended trot chapter of Reflections on Equestrian Art:

"The extended trot can only be obtained through extreme impulsion. For this to be true, it must be executed from the peak of collection in the school trot. It must be ample, and must not include any harshness or precipitation in the gait.

Even at maximum extension in the trot, the horse must keep his legs supple. The movement must not be rough. The so-called extended trot, in which the horse stiffens his back, gesticulating with his lower front legs as if "shooting his cuffs", pulling on the reins below a rider who uses his legs at every stride cannot be considered in the domain of impulsive, classical equitation."