I'm with Mr Aardvark here: the path is exactly that of a "Byzantine" throw: starts behind the body, launches into one rotation that leads to release (on the completion of the one rotation).

On Mr Mersa's vid, the rotation is behind the body rather than above the head, and the sling is longer than on the video which I linked to, but that is a minimal difference: the starting point is the same, and from there there is no other "flight path" solution: you can't go straight into the throw, so the sling describes one rotation to build up tension and speed-- it's the minimum and only solution for the throw.

One might develop a notation for sling paths to make this sort of thing clear.

Yes, my understanding would be that Byz is hanging start from behind (=1/2 rotation) following by single rotation and release. Anything else is multi-rotation segueing into the release (the distinctions, helicopter, side-arm, etc, seem to me not hugely important); except for underarm, which has weaker release due to wrist positioning.

Right got it. Bit of a greenish blue , blueish green thing.
There's a variation there but not enough for a new colour and each colour has multiple shades.

The other style I was going to show is what I call a southpaw Apache. Standing right hand froward right hand throw hold sling with pouch on left of face and hand above head flick wrist back and whip down foward into Apache , not powerful but very good close range accuracy, thinking sling golf putting.
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