While you're thinking about Body Doubles, look into Dr. Beter, Organic Robotoids and the Jimmy Carter doubles.

In particular, Audio Letters 45 to 50, featuring verifiable reports from the 70s about the Jimmy Carter doubles (which references a September 79 issue of Sports Illustrated showing the Jimmy Carter switch, compare for yourself, issue is on archive.org),and discusses the various cloning and cloning adjacent technologies that resulted in these beings.

Just as future proves past, the past is also necessary to understand the future.

These audio letters will explain why the Carter/Biden/Clinton doubles function the way they do, why there can be multiple models that all seem to rely on a version of the same memory, and why their memories are often faulty and they misremember things on vast scales.

It will explain why these beings don't sweat, but it will explain why they need constant cooling and frequently malfunction on camera.

I imagine cooling technology has gotten more compact since the 70s, but I often wonder if Hillary's penchant for big pantsuits and weird baggy clothes was a way to hide a more obsolete cooling technology?