Dr. R. D. Scoggins, equine Extension veterinarian at the University of Illinois College of Veterinary Medicine in Urbana, believes imprinting can be beneficial if done right, but dangerous if done wrong. Dr. Robert M. Miller, a veterinarian from California, made imprinting popular again. Imprinting can prepare the foal to live in the human being's world and tolerate a lot of the things we do, such as inserting a nasogastric tube, placing a rectal thermometer, clipping the body, working with the head, or trimming the feet. However, he believes people can go too far. Sometimes people try to see how many things they can get their horse desensitized to until, eventually, they get the horse desensitized to life.
Some people get their foals so submissive that the foals end up with no protective mechanisms.
The flight syndrome, for example, is used to teach a horse to lunge, to ride and go forward, and, for racehorses, to move out of the starting gate. If you take the horse's natural reactions away, you might as well ride a horse on a carousel that's not rotating. Another concern with imprinting is restraining the foal. Some people don't like the fact that the foal will have to be submissive for the short time it takes. Frequently, the foal struggles and people release it, which teaches the foal that it can struggle and get released.