Cavaletti to vertical - take 2

Today we worked on the same three cavaletti to a vertical (3'3" at its highest).  Once again, going right it was easier to go over the cavaletti, but harder to line up over the center of the fence, and jump it on the 20 meter circle (instead of kind of angled); and going left it was harder to go over the cavaletti, then easier to go over the center of the fence.
To go right, I had to counterbend Duke for a few strides, then bend him back as we did the final quarter of the circle (if fence is at 12, after 9), but I went and walked it after the lesson was over, and tried to move my shoulders to see what it was.  John said that Duke bulges his shoulder out to the left (why we're counterbending) when we go to the right, but he doesn't bulge his shoulder out to the right when we go left, so that's part of it.
But going to the left, John had to stand so I would ride around him, and then he put out ground poles to make the shape of the circle, and then it was easier.  So going left, I was cutting WAY in to make the circle.
I think - maybe - these two differences have to do with the way the exercise is set up.  Going left, you go over the third cavaletti then there are 7 strides to the fence, and then 20 to the cavaletti.  So there's an obvious "line" from the last cavaletti to the fence, but then I lose the shape in the empty space that is 20 strides.  So it's hard to get back lined up for that first cavaletti.
And going to the right, the fence to the first cavaletti is only 7 strides, so again, an obvious line, but the third cavaletti back to the fence is 20 strides, so I lose the shape of the circle.
Huh.
So I think at home, the way to work on the shape of the circle would be to put out ground poles and then try to ride over them on a circle in the correct arc.
Eventually, going left, John took the cavaletti and moved them all about 6" "closer" to the first one, which changed the angle ever so slightly (instead of the middle cavaletti lined up with the corner of the arena, it was slightly off set), and then it got way, way easier to ride.  John said that the line just looks different - it looks more like a straight line instead of the arc of the circle, so I don't mess around with Duke trying to get the correct bend, I just ride through it.  Even though the distance is exactly the same.
John said that when Duke does the funny hopping skippity jump instead of just cantering over the cavaletti, I have to just deal with it (I was starting to get really frustrated, and I'd pull him off the circle and then walk and then fuck around with the trot for a while then fuck around with the canter for a while before I'd try again), I have to just confidently go to the jump anyway.  He said at prelim, especially corners to skinnies, the distance is usually just a little off, and that Duke is very good about going anyway, but I am going to have to put my leg on and ride it, even at the odd distance.
Duke got super sweaty, and was tired about half way through, but I think he liked the challenge.
John also said that it's different to ride that vertical at 3'3" and 3'7" - that the height starts making the turn and angle more significant.  I think maximum height today was 3'3", but since I struggled with the cavaletti and the right turn to the fence, we definitely weren't ready for the next hard step.