Thanks! The design is very simple. It's a 10 foot piece of 1/2 steel pipe placed within another length of 3/4" steel pipe, and welded together. At the bottom, is a solid 3/4" round rod, welded into the pipe. This round rod fits the forward seat mount, as well as the rear pintle mount of my jet boat, which I also use for my ski pole.
I fully expected the footage to be wobbly, considering the camera being on a tall pole like that. But to my amazement, it's pretty stable. I guess when you're underway, wind resistance is strong enough to prevent the side-to-side sway that would otherwise be there. Anyhow, I definitely plan to do some more videos with the camera pole!