Based on what you guys are telling me, I'm thinking there's five distinct situations which call for distinct solutions:

1) Cool (not cold) wet weather - bread bags over socks.
2) Cool dry weather - no barrier necessary
2) Cold dry weather - VBL under socks (over thin base).
3) Warm/hot weather, wet or dry - no barrier, just deal with wet feet.
4) Cold wet weather - I don't know, buy boots maybe?
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