If the horse has a soft-focus, a quiet mind, can follow the human's feel with no trouble, and is okay to have its thoughts interrupted with a new idea, then I want to know more about the trainer, the philosophy, and methods. If those things are working well for a horse, the method can’t be wrong for that horse at that time.
Horses Are Literalist
Science-Based Training
The bottom line is that I believe using the “science” tag is nothing more than a marketing strategy. As a person trained in the rigorous sciences, it bothers me to see something as beautiful as good science exploited in this way. Despite the nice idea of using methods backed by scientific data, in reality, nothing changes for the horse or the trainer or the owner. Good trainers will still be good and bad trainers will still be bad irrespective of the science behind their methods