I don't remember when I learned about it or how verifiable the source was, but I knew it too for at least a decade. I am a radiant, heavy-breathing, sweaty target. I have outclassed everyone I've ever met on the mosquito attraction scale. I've used loose longer clothes but thought it was just stopping their bites from reaching my skin. I didn't think about how it could also be diffusing my thermal appearance since I'd still get bitten on exposed areas like face and hands.