so to make ice melt, you add heat. when water freezes and turns into ice, it releases heat. farmers use this knowledge to protect their crops in the winter. orange farmers actually spray the oranges with water and allow that water to freeze, and this in turn keeps the oranges warm during the winter.
know what does this have to do with biking:
while riding in philly's wonderful winter mix tonite with my soft shell, a lot of water/snow/ice was starting to rest and melt on my arms. i thought for sure my arms would freeze and cursed myself for not bringing out the goretex shell. anyway, the ice/snow/water ended up freezing and that frozen shell on my arms actually kept them warm.
know what does this have to do with fixed gear:
i was one on when i learned this.
just wanted to share. im not saying that the freezing kept my arms warm, it was most likely just that the layer of ice blocked 100% of the wind, but still i think these things are connected somehow.