RE: Rudder inputs on belly-side knife edge.
This is one of my favorite things to work on when I'm on the simulator. I saw Chip do it many years ago in real life and remain impressed to this day.
I have a problem getting my magnitudes down more than direction...some airplanes just seem to do this better than others. I think the trick is to use minimal elevator.
I've got the AeroflyPro also and lately I've enjoyed this most with the Zlin. Give that one a shot. And the lower you fly, the better.
I assume you fly mode 2, Herb. I don't know if that's a handicap or not, but with mode 3 your right stick follows an oval path when slow rolling and I find that easy from the 'muscle memory' standpoint.
Burn fuel, electrons.
-Ron