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I obviously like this explanation, but particularly because it leads onto an easier appreciation of what happens when airflows get really vigorous (around Vne) ie the masses (the air-particles) whack even harder into the leading edge of the wing (and so "bounce" correspondingly "higher") - and consequently have even less effect on the top-trailing edge of the wing. At the same time the fast flowing air-particles are hitting the underside of the trailing edge with "maximum" force. These three (increased) "effects" act in the same sense; to reinforce each other in the (additional) torque they apply to the wing spar.
Hence the need for Vne - the wing spar just won't like to be twisted beyond this point!
I like "Thinking Physics" but I've always been a bit of a fan of American teaching books. It always seems to me, many of our writers want to impress other academics. The Americans only think a book is good if the student learns.