[mtw]

all of this tech and no mention of warm hats. anyone living in cold countries know most of the heat is lost through the hat.

and drafts! any draft will make you cold, even if you heat your home at a high 24C

[mikestew]

anyone living in cold countries know most of the heat is lost through the hat.

Those folks think they know. What they don't know is the "X% of heat lost through your head" myth is based on a poorly-run U. S. Army study from the 50s. I'd provide a link, but it's trivial to search for one from a source of your choosing.