Soften the gristle

We had a jump lesson on Friday followed by a dressage lesson on Saturday.  Although a change from normal, this had some benefits.  John noted that Duke would be stiff for dressage, following his hard work jumping, and that gave us an opportunity to work on how to soften the stiffness.  This will be something I'll want to do on show jumping, following cross country.
John said to start with 10 extra minutes of quiet walking around, away from the hustle and bustle of the show ring.  Follow that with some big neck bends - a big wide open inside hand, and giving with the outside hand to give him enough room to bend his neck.  Use inside leg to push him round and let him bend around it.  Duke could bend easier to the left than the right, so keep working with him until he gives in the neck.  John said this will help him loosen up the stiffness he carries in his front shoulders, and in his hind leg - his right hind, I think, mostly.
This took me opening my hand far wider than I was comfortable with and then opening even further.  I know it will be hard for me to trust that process at a show, so it was good to feel it in a lesson.
Duke was good, but it was easiest to feel his stiffness at the canter, where he wanted to stick his neck up, rather than move over the top of his back, so that will be another clue to me that he's feeling stiff and uncomfortable, and needs the time to soften up.
John said that Duke is like gristle; he's wiry underneath, and needs to soften up those kinks to move more freely.
We worked on 20 meter circles and leg yields off the quarter line.  Some of these, Duke crossed nicely, and others we kind of drifted at an angle sort of towards the wall.  I think the difference had to do with the outside (wall) hand, although I'm not sure if it was using it as a wall (a half halt) or giving a little that helped Duke square up his shoulders and cross.  He popped his head a bit on the down transitions, but I was thinking in both lessons how much better balanced and even he feels than when he got here a year ago, and how well he tries to communicate with me.
John had me change my leg aids (more on the inside; forward and more on the outside), but this part is still beyond my grasp.  I can (mostly) do it when John is telling me, but I can't feel it well enough to know when I should do it on my own.