Dressage after the "incident"

On Monday, Duke was a little rowdy and then declared he was completely and utterly lame in his left hind (and if he put weight on it, then on his right hind).  Tuesday he got hand walked, Wednesday lightly ridden, Thursday a bit more, Friday a bit more, and yesterday a dressage lesson.  He was tossing his head when he picked up the canter Wednesday - Friday, but not with John there, although John did have to walk next to us at the start with his hand on the inside rein to get Duke round and on the bit (and then he stayed there, pretty much).
We worked on using the leg to do down transitions, halting, then walking again, and twice a rein back.
Take aways:
For hand aids on down transitions, it isn't a heavy contact, but a squeeze and release while I am closing my legs.
For halting, soften my hands once he halts.  (Thanks to John, Duke then drops his head.)
For rein back, tilt forward on my pelvis, then pick one side, then the other.  Duke did these fine.  Well, he did the first one great.  The second one we went in a curve.
At the canter, he needed to be more round, and this is a half halt with the outside rein, and then a bit of give and release with the inside.
After John has ridden him, Duke's back is much more lifted, he's much more quick to respond to the aids, and he prefers for me to ride him off of my leg instead of off of my hand.
Great lesson, but John said not to jump him until Wednesday, just in case it was tying up, so that everything works out of his system.  He said sometimes a horse can make himself so anxious that it looks like tying up.  He also said that letting Duke rip around to get his ya-yas out isn't ever going to work.  I'm going to give him a similar workout today, John will give him a harder workout on Monday and Tuesday, then we'll try jumping on Wednesday.