Say what you want guys- when a so called pretentious, arrogant, pompous so called "climber" comes onto a site that is composed of other climbers with their own experiences (and might I say FAR superior skillsets), and has the audacity to proclaim that cotton is the way to go, then continues on spewing forth his "formal" education credits, it's time for a CALL OUT.
Pretentious, arrogant... It is what I think... you didn't bring any argument to your point of view.
A sponge??? a sponge absorb the water and keep the water inside the cotton layer. When you climb a route like Lincoln throat pretty fast, your T-shirt is going to be wet, but not the other hydrophobe layer (that means that the wool, which can loss 50% of his isolating capacity by conduction, or any other synthetic isolation, stay dry). You change the T-shirt and you still have a dry layer outside the cotton which is dry. Without sponge, the water migrate from a high concentration inside the first layer to a low concentration on the last layer, it is a flow of water and heat that you lost As a beginer belay, he is waiting in the cold...wet because the water is not evaporated immediately, but slowly. Whit the cotton, you are dry because the other layer are hydrofuge and the water is absorb by the cotton.
Diver suit are made of polypropylene. The water is trap inside the coat and the cold water can touch the body. It is an application of the sponge technique.
cotton cause many accident due to hypothermia. Particularly those people who hike with jeans or climb without t-shirt. But if you can take out your transpiration without deterioration of the isolation of the exterior layer..., you use the cotton's water retention as a sponge....an the other layer stay dry. So, as a sponge, cotton is good, as an exterior layer or isolation cotton is very weak. You can use a cotton t-shirt and an hydrophobe t-shirt under thermal imaging cameras and see the heat loss of each.
Further more, I told people to try the cotton before in safe place. For example, bring six people without knowledge of this conversation to Havard cabin, asked them to wait for three hours in the cold without large movement like in a belay. Do the same experience with synthetic layer. You will see who is the fucking fool!!! In very cold day, you can probably measure a significant difference between the cotton (warmer) and the synthetic (hypothermia). You are going to have a deep understanding, not an assumption without understanding of the process.
Deep understanding and superficial knowledge. It is the debate here. I red the sponge principle in a book from Everest from around 1960. Cotton act as a "water layer" that air can not traverse. an other point of discussion is the use of plastic bag in climbing shoes to prevent the insolation of the boot to be wet. Some agree, some not.Note cotton can be very dangerous. In a case where it is very windy and you have to keep the wet t-shirt on you, you risk a lot. Other technique are also important to stay warm. In general, a beginer wait an hours at the bottom of the cliff or more. Don't compare yourself with experience climber who start in fifteen minutes. It is why I said previously that some solution are good for some one and not for other.
reference: see the text on familarity heuristic. every body do it, so it most be true... not always true.