I'll see what I can dig out when I get home. Yeah tweed is good up the hill (for me) blends in (if you get the right tweed for the background), quiet, comfy, weather resistant, fire proof and less likely to cause suspicion than DPM.
Some of the outfit that was on Mallory's body consisted of tweed, and on lab inspection it was noted that the tweed was of such a good/special weave that they recon his outfit as a whole would have been comparible weight and performance wise to a lot of modern alpine kit.
Heres a
LINK to living legend Brian Blessed in his Everest attempt in tweeds.
Cheers GB.