Because I work in the coating industry we deal with finishes that "wet out" that is if you place a drop of water it basically just lays there in an irregular very non-bubble shape.
Try this at home kids: take a drop of water and put it on a piece of plastic like a tupperware lid, so that it makes a bead. then dip a toothpick in liquid soap and touch the bead of water, then boom it wets out. That's the soaps ability to make water "wetter", or called wetting out. It's ugly on cars and it's what happens when the car is stripped of all its protectants (or a good test to tell if the car needs more wax).
So with the experiment we established that wetting out is not sheeting and is definately not beading.
Now sheeting action and beading are really more similar than we think. The mechanism is the same but the results are different. Both are due to the surface tension of the water. The only difference is the size of the water droplet. If it is small it beads and sits there, if the droplet stays big then all the water molecules pull all the other ones with themselves.
I really think sheeting and beading are the same. Spray a nozzle on my car you get water beading. Use the hoze without the nozzle and you get sheeting (and some beading). In either case the Klasse is clearly there. Now put some P21S on my car (as I did on my wheels that were Klassed) and you get complete wetting out squeaky clean yuck. That's what you don't want, and that's what you finish approaches as your wax starts to diminish, wetting out not sheeting. (hope that helps, just my theory)
Who know's maybe sheeting is step above beading, not only is the wax so hydrophobic that it makes it ball up in dropletts but it does so in a way that the droplets are maximized and so then the maximized bubble just falls off the car, which in theory is way better than non-maximized stable smaller droplets that just lead to little spots.
(remember attempt to answer the question, then expand

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