The little finger (not visible) is what's holding the fiber. By pulling the fiber hand away from the drafting hand, the fiber thins out as it passes through the tunnel from pinkie side to thumb side of hand. Fiber rides over ring finger with just a teensy bit of tension from riding on it, then straight through (no contact with middle finger) to thumb and forefingers which are stretched out to form a "beak" that can pinch the twist.
Shot this back toward myself from the other side.
The below photo got flipped on its side somehow. so right side of photo is actually vertically downward. This photo is backlit to show funnel that comes from interior of wad of fiber. Note: There is no twist in the funnel whatsoever. It is fibers from INSIDE the fiber mass that seem to grip onto what's been drafted, as though what's been drafted is acting as a leader, pulling it along. At this point the fiber seems to draft itself, and the funnel starts coming straight from the little finger's hold. I don't thin it out with thumb and forefinger, at all. That's already done and the thumb and forefinger's only function is to pinch off the twist with the fiber hand so I can release it with the drafting/spindle hand.
Please see this swirl. Here I had to let go of the pinch with my right (spindle) hand to hold the camera AND wanted to show the "beak" I'm forming with thumb and forefinger, so in this shot you will see some twist did get into the wad of fiber.
But more importantly, the photo shows how defined that weird funnel actually is. It goes straight through into the core of the wad. (???????)
Eventually, when I'm at the end of the wad, I have to stop and straighten out the fiber mass. My sense of it is that what it wants to do (I THINK!) is invert itself and become the last part of the funnel, but there's usually uneven blobs attached that prevent that from happening.
Bottom line is that when the drafting is in motion, I'm not touching (let alone gripping) the fiber with any part of my palm or fingers EXCEPT that the pinkie is curled around it, and maybe a little of the ring finger, though as far as I can tell, the ring finger doesn't contribute tension other than the fiber funnel riding over it.
Here's another photo of the funnel, with the mass being held down by a remote in absence of my drafting hand. I shot it with daylight backlighting and no flash so you can see through it. The funnel continues on into the mass as a darkened area. I am sure it doesn't have twist in it, because I have no problem thinning it out if I wanted to, and I wouldn't be able to do that if it had twist. Yet if it doesn't, I am totally STUMPED why that dark area can continue this far into the mass! It's looking to me like it's actually curling right around within the mass if that pink tinged area I'm seeing is "funnel-yet-to-be." And it sho do look that-a way.