I also belong to wintertrekking. I think Rick put a link up here a while back. I've read almost all of the articles on clothing and gear and looked at what the sponsors sell. The focus is on traditional materials because that is what works for them in those conditions, although some members have modern clothes such as parkas and base layers.

What is surprising to me is that under some conditions-dry and extremely cold-traditional materials like cotton for outer layers work better than modern materials and footwear like mukluks work just as well, if not better than modern boots.

It just shows that what you need depends on where you are, when you are out and what you are doing.