[QUOTE=alicen;8095748]
I am kicking myself for not bookmarking the Carl Hester clinic in which he says that most people use long and low briefly at the end of a ride or for a break, but they should be using it to work the horse.[/QUOTE] Alicen, this may be the link you referenced. This is the one with Carl teaching Carlotte on a 5 year old. At around 16:24 he starts talking about stretching. One thing he says specifically is that the horse stretches best at the end of a ride, but we should not just do one circle stretch and stop, but rather to continue riding in the stretch position so that the horse gets used to it and can then do it at the beginning of the warmup.
This link is sensitive, but stick with it and it will eventually play the video.