Right now I have a big black Standardbred named Bailey. We saved him from a horse rescue becuase he wasn't good at racing. They told him I'd never be able to train him to canter... He had been trained well with a big whip to NEVER canter racing or not. I didn't think this was true. I brought him back to my barn and worked with him little by little every day. When ever I clearly asked for a canter, even on a lunge line, he would understand put his ears back and keep trotting at almost galloping speed. Finally one day I came in without the whip for lunging. He eyed me putting the whip down he calmed down instantly his ears went up again and he seemed to take a bid horsey sigh, :) . After nearly 45 minutes he cantered!!! It was only 1 stride but he did it. After the stride he quickly started trotting again. I let him stop and pampered him like all day. Still now I can only get him to canter a few strides, riding Or lunging. But he was such a hard loyal worker and still is, he'll jump walk, trot, do trotting poles, but never canter. Standerdbreds are great horses, just for some advice don't get one who raced if you want to canter or do showjumping/dressage, even if they are the sweetest horses ever!