A question about base layers for very cold weather

Seems to me one question to ask is whether, in the conditions you expect, those would ever be too warm. In colder seasons I aim for my base layer to be the thing I never take off, so in the warmest conditions I would expect on a given trip I will be down to just the base layer while on the move, and if I get it right I will not be too warm. Also there is the moisture transport factor – would those perform well in that regard? Gut level , I’d say they will not if compared to  something fleecy.

If you are traveling in extreme cold, you are either skiing or snowshoeing, and maybe towing a pulk. You are going to be working hard, I see some sweat as almost unavoidable, as it is difficult to manage your layering so precisely that you never sweat. So coping with that sweat is critical.

I have recently gone back to fish net base layers (remember those from the ’70s?) for winter warmth and moisture management. The Norwegian company, Brynje, makes probably the best version (pricey though). The trick is to wear a snug fitting next-to-skin fishnet layer, and wear a somewhat snug wicking layer over that (merino likely is best, due to its efficient ability to transfer moisture away from the body).

The reason this works so well in cold weather is that your perspiration wicks away to the merino, with the warm vapor being trapped in the fish net voids. This keeps your body much warmer. When I tried this on a snowshoe day trip last winter, I had to unzip my medium weight synthetic parka and GTX shell so as to not overheat when we were going uphill. When we were just sitting on a log eating lunch, there was no overheating but I was still warmer than my partners.

I thought it was worth asking as they are lighter and pack down smaller than my PowerStretch loose tites