The illusion is sufficiently distracting that I've been asked to not have it be automatically visible.
What's remarkable about it is that people have a wide range of reactions to it-- whether it moves, which part of it moves, how fast it moves, and whether it matters whether one is looking at it directly vary from person to person and from time to time for the same person.
I can't see it move at all, but I'm willing to take other people's word for what they see.
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