Some years ago I saw an ad for what I think was called commuter long johns. They were designed for someone wearing a suit (at least that was the picture with the ad) who worked in an office but had to be outside for short periods waiting for the train or bus. They were basically long johns that went down to just above the knee. Kept you warm on the thighs but let the calves breath under your pant leg.

I can't remember where I saw the ad. One of the bigger men's stores I think (Brooks Brothers?)

Mike