Wow, EnglishBob!  That was a fantastic explanation of my problem.

Thanks so much, yarp!  I am sure that P3DO is a great tool, but does it still create those extraneous keyframes as EnglishBob was describing?

I suppose I should file a bug report with SM.  I currently have a more important bug report out for an even more obscure firefly rendering problem, so I'm inclined to wait until they respond to that before filing another.  Maybe that's silly.

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