Rocketman -

your comments reach the level of absurd. Crowds POUR into the stadium as well but I suspect that the motion post-entrance choke is Brownian.

It is unfortunate that you are not capable of understanding that choke effect is nothing more than the resolution of vector forces within a collection of interacting bodies which are subjected to a variety of external (and resultant internal as well) forces varying in both direction and intensity. This could not be simpler in concept tho admittedly complex in regard to the number of bodies and variant forces. I'm sure that with today's computational forces it would be NBD to mathematically model and display it as a nice slo-mo vidi so you could actually see it happen. You may scale that in any way that you like, micro or macro, but it remains nothing more than a 3-dimensional pooltable-like vector analysis. And you can call it fluid all you like and it still is a simple vector resolution of interacting bodies.
BTW all that "semi"fluid is of course a misnomer as it is actually "quasi" or more properly "pseudo" if you feel absolutely compelled to insist on that ridiculous reference.

That's it for me. I don't know any other way to attempt to convey the physical reality of this choke thing.

So, thanks for playing - - - I'm off to practice my fire-hose clay target technique. I'm sure my new appreciation of shot column fluid dynamics will be of some great assistance.

Dr.WtS
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