John Gann wrote

Which way works better? Does the "shiny side" go in or out? Inquiring
minds want to know!

John, always remember shiny side out!

If you wear the tin foil protector shiny side it will set up a
harmonic resonance with the fillings in your teeth and attract
flouride from your drinking water to your cerebral cortex, turning you
into a raving pinko commie libral decaf drinker.