The poor man's rear

John explained everything.
Duke gets nervous when he hears noises and he can't see the source (what we thought was going on in November), so it probably was the horse behind the hedge.
Two things I could have done:
First, when he started getting tenser and tenser, on the long side, going away from the judge, give him the reins a little and let him relax his neck down.  And then, if he's still tense, just give up on the lengthening and just ride the canter (or trot) normal and take the hit on the score.
Second, when he goes backwards, bend my hands - JUST A TINY BIT - and steer him around in a curve.  John said that sometimes when their hip has to move under them, it breaks up the panic.
He said that thoroughbreds do this - they feel trapped and they panic and they freeze and they plant their feet.  It's fear, that's why I could feel his little heart beating under my leg - not being naughty.  And that smacking/kicking will not ever work, and might eventually make him rear, because the running away backwards was "the poor man's rear" which made me laugh for way too long.
Then he told me and Meg about his first Rolex, when his horse got afraid of the motor in a camera, and he did a gallop lap around the inside of the dressage arena before going back to his test (then going home, and buying one of the motors to make the noise at home).
He told me not to use reins/kick because he had three thoroughbreds in a row that reared and flipped on him - he said they're so frozen they just throw themselves down on the ground.
The other silver lining here is that until my lesson, I had completely forgotten that after the November incident, it took me months to get Duke to stand still in the halt again.  John had said I might just have to - really fast - halt-salute-be done, and so he's actually done quite well this whole show season for what we were starting with.
The whole thing made me feel SO much better, and I was so afraid that John was going to tell me I was a fuck up, which he's never done, so I don't know why I was so anxious about what he would say.  I guess I was afraid he was going to say that it wasn't a fixable problem, but instead, he knew just how to fix it, and - I hadn't been that far off in thinking about it.  I *knew* he was getting tense, I just didn't do anything about it earlier, and just knowing that will help us a lot in the future.

I thought jumping would be a good idea, and John said that if I had my dressage saddle, he was going to make us do easy circles out in the field.  We kept it low key and fun for Duke, so it was just going over a little plank a few times.  John said if he stopped I'd be in trouble, but Duke just popped over it like it was not big thing.
Then we did a vertical that had two poles angled on it, and each lap John pushed the tops of them (on the rail) closer together, so that we had to get more and more and more precise.  Duke also jumped this like it was no big thing.
Then we did a five stride plank to gate, and we rode this just fine so John had us stop there.  He said what he liked about that fence was that on stride 3, I saw the distance, and put my leg on so that we would make it.  He said he also would have been ok if we jumped in short and on stride three, I sat up so that we made it a six stride.
Then he showed the levels of riding, and he said the first level is that you just ride through the fences on whatever you've got.  The next level he said is the hardest, at this one, you see the distance but you don't ride it correctly, so you're just flailing.  He said this one is hard on everyone, and it's where I was about two years ago (I vividly remember the months of flailing, and how frustrating it was, and how he told me then that it was part of the process and to trust that we would get through it and then suddenly it would be so much easier).  The next level is being able to adjust about 6' out - you have some adjustability and can fit in that last stride in that six foot window.
From there is about 3', then 2', then 1', then you're at the Olympics.  He said at 1', you can put the horse in place for every fence so that they never knock down a rail.  You just get better and better at seeing where you want to put the horse.
So then I walked Duke around the cross country field where he got scared of a weed blowing in the wind, but other than that, was pretty relaxed.
We leave in a week for Montana, which is a day earlier than I thought, so it's going to be a tight week, and the next week, my timing was bad with the farrier, so he's going to have a couple days off the weekend before Montana, and then a few days off when we get back (!!).

I told John I didn't want to go to Montana and get eliminated and he asked what would Duke learn from NOT going to Montana.  (Nothing) And what does he need? (Experience) So he said the whole thing was why we definitely should go to Montana.  Good points.
I'm so, so, so lucky to be able to learn from John.  Good lord.