George, my previous bikes that had B17s on them were all drop bar bikes. I don't ride "bolt upright", but fairly upright in the parlance of typical Rivendell philosophy. Drop bars are typically at level with my saddle nose. I sweat on long rides no matter the time of year, but especially in the warmer months. I typically wear synthetic shorts with wool boxers... never any sort of chamois (because of the sweat, having a wet sponge between me and my saddle just increases the likelihood of saddle sores and chafing).
My Gus is a very upright position of course, and it has the wider, "city" Berthoud - the Mente. I am currently building up a Sam, which will have upright, sweptback bars. I may throw my old B17 Special on it, because it seems to be one of the thicker-leather variety, and has held up very well over a couple of decades.
Brian
Lexington KY