Hi Mark
Thank you for your feedback, very interesting. It seems that you “catch the cast” !
As you and your tippet noticed

, more you cast it on a vertical plane more you have to deal with line trajectory issues. More you cast vertically more difficult it is to cast forward while you are trying to produce a force from the right to the left : collisions must occur somewhere (by the way: never try to learn the svirgolato with a fly ! )
Actually, on a total vertical plane you should first obtain a “close loop” with the tail of the fly leg under the rod leg, everything in a vertical plane (and not the tail part of the fly leg above and to the left of the rod leg, in an horizontal plane, as in a “standard” svirgolato”).
At this stage, if you can control the trajectory of the tail (which is not a big issue with some practice), you have 2 options:
1. You direct this tail (the end of the leader, better: the tippet or the fly itself) in the water and lay down your rod. The final unrolling of the loop is stopped and the result is a fly landing first curve cast to your left or to your right, depending which side you have casting your “closed” loop. You can not really control this cast over 10/12 meters but it’s a nice trick cast in many fishing situations.
2. You let the fly kiss the water maintain some tension and don’t let the leader/line fall in the water : the fly kiss the the water and jumps forward as the loop finish to unroll. May be not excessively useful for your everyday fishing (who knows?) but funny stuff and excellent exercise. It’s the same dynamic of the svirgolato but in a vertical plane.
A suggestion for fellow students. Try slipping the butt section out and using it to pantomime the twisting movement and (especially) the timing in slow motion, then with slower motion and eventually normal speed. Repeat the exercise as required. Oh, and fwiw I found it worked better (more controllably) when I kept my elbow in and operated with something closer to the foundation or basic casting stroke. More variations to come
Thanks for the trick, I’ll use it for my teaching!
Take care
Malik