Thoughts on a weird/unique way to empty holding tanks.

I've yet to see an RV that sits high enough to have a tank dump connection higher than the height of a commode in a pit toilet. I guess you could get most of the tank dumped, but it won't empty.

I've never see pit toilets close enough to the campground roads to be considered useful for such a task.

If a camp host or ranger saw that activity, they'd surely have a few things to say about it.