Excellent dressage lesson

Duke had the vet last Friday, a light ride Saturday, and had Sunday through Tuesday off (round pen Tuesday and today) because he had an abscess (?) come out of his left hind hoof bulb.  His leg has been warm and swollen (worst on Sunday), but the bulb itself hasn't been bothering him, even after it burst on Monday.
I thought he would be a maniac, but he was excellent in his dressage lesson.  John took it up a few notches, so it was pretty hard work, especially sitting down yet tall and not leaning forward at the canter.
We did work on 10 meter circles (trot and canter), going forward, leg yields (to wall, abruptly to wall, and to wall and then back over), then 10 meter circles changing direction going down the center line, and 20 meter circles.
John had me work on bending him around my leg, and for one canter, I had to reverse the leg aids (inside back, outside forward) because his haunches were too far in and then his shoulders were going out.  John had to explain Duke's mechanics, but then it made sense, so that was pretty cool.
John said to ride him boldly; that if I ride him bold at home, I'm not asking him to do more at a show.
At the end, we did a halt and rein back, and Duke wasn't the least bothered.
It was a fantastic lesson.