More sweaty dressage work; sans draw reins

Duke and I had a nice hack out along the road, in the sunshine, before starting our lesson.  We worked inside, and it was quite a workout.  Duke had a sweaty butt and even a sweaty throat latch.  John said that's how hard I need to warm him up before our dressage ride at the show.
We started out working in half the arena; then John had me overbend to the inside, then to the outside, going down the long side.  I had to keep Duke moving forward while overbending.  From there, we worked on it on 20 meter circles, and then giving a little and then putting back together.  We did some leg yields each direction, and the bend there is the opposite of the direction you're going, so if Duke is moving to the right, which is off of my left leg, then his neck is bent to the left (towards the leg giving the over aid), not to the right (the direction he's going).
John said that when Duke gets "stuck" and locked in, the overbending is used until it breaks up his pattern, and then I can go back to regular riding.  Yes, it's ugly, and I wouldn't ride it in a test, but it's better than him going around with his jaw and neck all stiff and clamped into place.
We did some lengthening on the canter, and John had me push him much bigger than I ever would do on my own, but Duke stayed really balanced, especially compared to when he arrived last year.  Then we brought him back.
By the second canter, he was tired, and it was interesting, because it was the most tired he's ever been when I've ridden him (he's also definitely getting chubby, and it was probably about 70 out), so I had to start using more and more leg to keep him going.  He did, though, he kept doing what I asked, even though it was a bit of an effort.  I also did his conditioning ride yesterday, plus a few fences outside, and I was surprised how nicely he moved today, since yesterday was conditioning.
The main takeaways from today's lesson are:  don't be afraid to ask for more (more bend, more forward, more flexion, more over his back); use my outside rein to make him round and flexed (not the inside); use my outside leg aid a little further back than my inside leg aid; to get him on a nice curve into the corners, think like I'm leg yield aiding into those corners down the long side.
I told John I was a little nervous about Spokane and he told me that no matter what happens - whether  it is dressage or cross country or show jumping, we'll learn more about Duke and come back and work on it.  It's just a show.
I was having a hard time deciding whether I wanted to jump or ride dressage for my lesson, but I'm glad we did dressage because Duke felt so good, and it was just the right good feeling to think about to try to remember to carry through this week to the show.