Off the Beaten Path
Join Date: Nov 2013
Location: Calgary, Alberta, Canada.
Interest: Hiking, Backpacking, Skiing, Space History
Cotton? There is a reason for the saying "cotton kills", it's almost useless in the backcountry. It's also hard to imagine creating a any kind of high performance outer layer without some kind of synthetic material.
With the exception of greater availability of Merino wool products (highly recommend these as base layers), virtually all progress in high performance lightweight clothing has come from advanced materials and synthetics. Even down is getting a run for it's money these days. If 10 years ago someone told me I could have a waterproof, breathable, durable rain shell that weighs less than 200g, I would have laughed in their face.