Tempered the jumping a little bit

We jumped outside today, and Duke started out with his same ... eager ... approach.  He quieted down towards the end, but I think he just got tired, rather than me riding better.
John had us bend him to the right in the warm up - Duke was very resistant, and later John explained that he needs to bend and not just hang on the left rein.
We started over the plank, then plank with a pole, then a vertical, and then did an oxer - 6 stride - vertical, and we had some problems getting the line.  We had to halt a few times on the far side, rather than Duke motorcycling around the corner.  Then we turned left, then we made a figure 8, with a plank to an oxer, and then oxer to vertical.
Duke got pretty wound up, and John had us circle, then ride past it without jumping, then ride just the oxer without jumping the second vertical.  Then he had put up a guiding pole (leaning on the front of the oxer) and gradually inched it forward.  We did this fine while it was just a circle over the oxer, but as soon as we added the vertical back in, I jumped the oxer too far to the left.
Duke listened, in between the fences, but he was still very forward, and I'm pretty anxious about how the show season will start.  It feels like we've gone very far backwards since our great jumping this winter, but I'm not sure why.