Great canter!

We've been moving, so not only have I been exhausted and not riding much, but my back has gotten every muscle in it sore. So I wasn't expecting much from my dressage lesson this week, although maybe that's the secret to a great ride.
Willig has been really great each time I've ridden him - he's just so grateful I showed up, groomed him, and he got 30 minutes of exercise, and he started the lesson out the same - low level hijink at the scary end.
We worked on leg yield, and when it was dragging a bit, shoulder in using the wall, which improved it quite a bit, and then turning down the center line, leg yield, then switching to shoulder in.
Then we did some travers (?) which is almost the same as shoulder in, except his neck bends the "other" direction. Tiny difference, but feels hugely different to ask for and maintain (just because it's new).
Willig had just a couple of short circuit moments, and Mike had us ride small circles at the trot.
He also pointed out the same thing as Shannon - why don't I use my whip? He watched me ask for an aid, Willig would hear me, and decide not to do it, and then I wouldn't whip him. Over and over and over again. But when Mike said "whip him" and I'd give him a smack, he'd go right back to obedient, quick, responsive Willig. So I'm still lacking in the assertive department, which is just soooo weird since I'm not really a very passive person (I don't think).
Then we did some canter work, and Willig did this just spectacular, mind blowing canter that was not on the forehand, not rushed, even tempo, just amazing. Mike was like "wow - what have you been doing?" and I was like "well, not riding and my back hurts - exactly the wrong things!"
I thought it was a fluke, but he did it again, and then again the other direction (although not as well, I think he was getting tired).
So the take aways were:
Work a bit on the travers - the feeling of his hind leg crossing underneath him - ride it off a circle and make a circle, and feel where that outside hind leg is.
Keep working on the canter.
Work on sitting trot without stirrups to continue to improve that.
Work on quick, consistent, obedient, responsive aids. A smack with the whip if he knows what I'm asking for and doesn't do it.
There was a LOT more - it was another chock full of lessons lesson, but I couldn't get to the computer for a couple days, and it was also so much cool, new stuff that it made sense while I was riding it, but I was thinking at the time "I'm never going to remember all this!"
It was a great lesson. Way to go Willig!
And he was good for J jumping him this week (outside)! and the hives are almost gone again. Mystery hives.