For further research: Impact Of Wet Underwear On Thermoregulatory Responses And Thermal Comfort In The Cold.
In the wet condition 175 g of water was distributed in the underwear prior to the experiment. The test was done on eight men (Ta = 10°C, RH = 85%, Va < 01 m/s), and comprised a 60min resting period. Skin temperature, rectal temperature, and weight loss were recorded during the test. Total changes in body and clothing weight were measured separately. Furthermore, subjective ratings on thermal comfort and sensation were collected. The tests demonstrated the significant cooling effect of wet underwear on thermoregulatory responses and thermal comfort. Further, the tests showed that textile construction of underwear in a two-layer clothing ensemble has an effect on the evaporation rate from clothing during rest in the cold resulting in a significant difference in mean skin temperature. The thickness of the underwear has more of an influence on the thermoregulatory responses and thermal comfort, than the types of fibres tested.
Oh. My. God. See, THIS is why I read your blog, dude. Excuse me while I go snort my coffee out.