What does Clinton Anderson say about horses that scramble or panic once inside the trailer?

Horses that scramble or panic once inside the trailer are a different problem from horses that won't load, and Clinton Anderson addresses them specifically in his Downunder Horsemanship program. His diagnosis is almost always that the horse was loaded before it had enough confidence in the space, and it now associates being inside the trailer with the panic it felt during that first experience. Anderson's approach for the scrambling horse begins with a critical distinction: the horse must first load and stand calmly with the divider open and the rear door down or open, before any attempt is made to close it in. He teaches handlers to feed the horse its hay or grain in the trailer with everything open, doing this repeatedly over many sessions, until the horse walks in, drops its head, and eats without concern. Only at that point is the divider introduced, and only after the divider is accepted does the ramp or door come up. For the horse that has already developed the scrambling habit, Anderson uses a step-by-step desensitization process where the horse is asked to stand in the trailer with the divider open while the handler creates low-level stimulation — touching the walls, tapping the floor, moving around — and releases whenever the horse stands still. The horse learns that stimulation inside the trailer does not mean it needs to move, which directly addresses the panic mechanism. Anderson also addresses the handler response to scrambling, which is typically to immediately open the trailer and let the horse out. This, he teaches, rewards the scrambling. He instructs handlers to wait until the horse has stopped moving — even briefly — before opening the trailer, so that stillness, not movement, is what opens the door. This single correction, applied consistently, resolves most scrambling problems within several sessions because the horse learns that stillness is what produces escape, not escalating movement.