My job is to help Duke out

My main takeaway from Young Riders is that I'm not helping Duke enough; this has something to do with half halts; but I'm not quite sure what I'm not doing.  And I think I need to figure it out to be able to ride prelim.
He was ok in dressage; some of our scores were quite good and a few were quite low (but different than the other low scores).  He got tense when it started raining, and I didn't have quite enough time to get him to relax again.  I thought his lengthenings didn't show enough difference, but the judge was ok with the up, just not with the back down.  His trot lengthening was almost nonexistent because I was so afraid of what happened at Whidbey, which of course didn't happen again at all.
For show jumping, he was a little crabby about being ridden again, and then again about the rain.  John said the heat is his delicate skin, I think the rain is the same thing.  When it was raining he stood in the trailer with his nose only just barely aligned with the side, so the rain drops wouldn't get on him.  It was funny and pathetic.
So for show jumping, the course was set funny (John said 9' strides) so the distances were either long or short, but all just a bit off.  John - god bless him - told me just before I went in to get him round and on the bit and to shorten him.  And it made perfect sense, but hadn't occurred to me.  All that I thought of was go long or short.  So that helped tremendously.  We got two rails, but that was still better than at Rebecca, and the ride felt pretty good, AND watching prelim it was just a massacre of rails, so I was pretty happy with that.
For cross country today, Duke was a bit of a pistol in the warm up, just kind of crabby.  I think - maybe - his hind legs are feeling just a wee bit tight.  John worked us a bit, and had us do a gallop so we could come back from it.  Duke LIKED galloping.  For the course, we rubbed several of the fences pretty hard, but he jumped everything on the angle I put him on, and it rode pretty much like I wanted it to.  The sticky fence was #14 (out of the water) and it was just a funny angle in deep footing, and although Brooke told me how to ride it, I didn't get him turned quite as much as I planned, but bless his heart he jumped on out of it.  So this makes every show except Spokane I've felt ok about the fences, felt like I was seeing the lines and tricks and knew what to do, and not getting too nervous.
John said that we were a little too fast and flat at the start, and that I need to work on getting him back on his haunches (not slowed down, just rocked back), especially in the combinations.  He also said that Duke is going to get aggressive and racehorsey after he starts going faster, and so when I'm going back to the barn, take my time and lollygag around so he doesn't get quite so worked up about it.
I'm happy with Duke.  He tried his little heart out, and although we're still figuring each other out, and the being [this close] is kind of frustrating, I think he and I are going to be a good team.
It did not help that I only got four hours of sleep Friday night and had to work Fri, Sat, and Sun instead of being able to focus or do the other 1 million things that need doing.  So that was pretty irritating and frustrating.
Thank god for John.  He just reads me and knows Duke and knows the fences and the course and tells us what we need to hear at the time we need to hear it.  He's awesome.