I do so love a lesson in which my ass is completely and thoroughly kicked, and that's just what we got yesterday.
I had to do a relative minimum of nagging to get Tristan moving forward, and he reached beautifully for the bit way, way earlier than he usually does. I was already counting the warmup a success, and we hadn't even gotten into the hard work yet.
First thing we tackled was getting him straighter through his whole body; he has a tendency to want to get a bit overbent in the bridle, and when I straightened that with the outside rein he threw his haunches in. So we worked for a while on really getting him straight and through, which to me felt almost a little bit counterbent. I've gotten too used to him overbending.
After that, we played with shoulder-in and leg-yielding to loosen him up. In the shoulder-in we focused on pushing from the hind end and not letting his neck overbend and his shoulder come in too far. In leg-yields it was all about small, quality steps and really maintaining the straightness. Shoulder is supposed to lead a teensy bit but not nearly as much as he was trying for; S. wanted me to allllmost think haunches in during the leg yield. We did both straightforward quarter-line-to-wall ones and then went out from the wall to the quarter line and back.
Finally, we cantered for some time and worked on getting him really forward and attempting some straightness in the canter. He was very tired afterwards, and had sweated quite a bit - all down his neck and chest, and on his face. I spent a fair bit of time rubbing him down with towels and checking on him under his cooler, but he dried off relatively quickly. It was warmer (in the 30s) so hopefully that's why - I still really don't want to clip him!
1) Work on getting him supple behind the saddle and continue that through our rides. If he feels like he's locking up or lagging behind, throw in some leg-yields to break that up
2) Don't hang so much on the inside rein in the canter, and work generally on keeping a more stable rein length and hold throughout all gaits and especially through transitions.
3) Pick a spot - or a feel - that's easily attainable for us now, but still quality work, and back off to that to end each piece of our ride. For us right now that's a forward, on the bit trot with about a Training-level self-carriage.
4) In the canter, try for counter flexion down the long sides and then back to the correct flexion for the short sides to inject more of a feel for straightness. It's a LOT of work for the outside aids right now but it will keep adding up.