He's saying that
because the chain can be thought of as a series of rigid poles, when you lift one end of each pole, it wants to rotate around the centre of mass which means the other end pushes against the surface, imparting an upwards force. These forces add up, being larger with the speed you pull the chain, leading to the chain leaping from the surface.
The rest of the effect is the natural tendency of a chain to follow the route taken by the previous sections.
This is why he says there has to be a minimum bend radius, so that the chain will act like a series of poles, not just a flexible tube.
Mould asserts that it should not happen with rope and some surface is required, technoboom is trying to show the effect is still there without a surface or minimum bend radius.
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My Name was saying these words inside your head on, Thu 2 Sep 2021, 10:53,
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