I started out by picking up the canter on the circle which is easier than on the straight. Right away I had to slam him down to a halt. It's not fun, and it borders on scary. On a circle, Speedy doesn't really change his pace; on the long side he sees open ground and tries to bolt. JL was very pleased that I didn't let him get away with it. However ... repeat, repeat, repeat.
I finally asked what the heck was wrong. JL asked how much inside leg I was applying. Hmm ... none? Problem discovered. I love Speedy to pieces, but he is SMART! Over the last few weeks he has learned that he can't "bulge" his ribcage out against my outside leg, but now he's doing the opposite thing. Essentially, when I apply that outside rein, he has been fishtailing to either the left or the right with his hind end which allows him to ignore the outside rein. Neither is acceptable as he doesn't have to work if he's not square on his butt.
As soon as I realized that he was now fishtailing in when I applied the brake, I was able to to control his pace more effectively. I asked for the canter, moved my inside leg back, and he swapped leads. Darn! repeat, repeat, repeat.
After some trial and error, I was able to ask for the canter while applying my inside leg just a hair to keep him from swinging in while I asked for a slow down with my outside rein. The first time I did it right, he came to such a hard stop that I was nearly tossed over his front end. This illustrated very clearly that my previous outside rein aid was ineffective because he had just let his butt fall in rather than sit back. Once I was able to keep him in a much narrower channel between my legs, neither falling out or in, he got my HALT message loud and clear!
From that moment, our canter got much better. Throughout the whole lesson, JL kept remarking on the improvement in our canter departures. Apparently it was quite obvious that I was keeping him straighter and had a much more consistent contact. In fact, the whole right lead canter has improved so much that we are now better to the right than the left. But, of course. There's always something.
So the idea that I am working on right now is narrowing the channel between my legs to keep Speedy on the straight and narrow. And metaphorically speaking, if there was a horse that needed to be on the straight and narrow, it would definitely be that gray pony!