A-Twist vs B-twist - TrickScience ep. 6

What are the separating factors between B-twist and A-twist? How can we see the difference? How can we measure it?

HERE IS AN IMPORTANT POINTER THAT I LEFT OUT:
  / b0xuvx_gmpo  

Yes B-twist is ideally horizontal and A-twist is completely invert. But tricks are rarely exactly what they are supposed to be in ideal conditions. This is why we need ranges regarding for example inversion levels.

Do you agree with the system I represented in this video when it comes to separating "Aerial family tricks" from "Butterfly family tricks"?
I chose the represented takeoff inversion ranges both based on the practicality aspect: Dividing all the potential inversion options on the 180 degrees scale into 45 degree "slices" (example at 3:21) is easier than figuring out some other thresholds. These ranges also seem to be working out well when it comes to the actual tricks and their looks.

Conclusions: B-twist can be done on many inversion levels but only a few got represented in this video. The range is bigger than for A-twists. The chest direction from side to side make B-twists horizontal right after the takeoff but they can start inverting a little more after that depending on the technique used. A-twists are characterised by the chest not moving to the side too much and being invert enough after the takeoff of the move.