You'll find that 8 yards of wook wrapped snuggly around your midsection holds in quite a bit of warmth. Warmer than trousers I find. Like mittens, everything is working together to produce warmth, rather than isolated like gloves.

Also, don't be confused about contacting your clan chief. You aren't seeking permission to wear the tartan, just finding out which tartans your clan recognizes and accepts as representative of the clan. Rather than trying to reach the chief, I'd suggest calling the local area's convener. Not only will he give you lots of clan and tartan info, but he can get you a membership to their clan assoc, and info on clan happenings.