I've used VBLs occasionally on my hands and feet for many years, and occasionally (usually inadvertently) slept in things that were effectively VBLs. More recently, I've been reading here and elsewhere about better-planned VBLs and their advantages, especially in cold weather.
What I'm wondering about relates to the trapping of moisture, sensation of clamminess, and effects on skin. For those of you who are VBL advocates, when does your skin get a chance to dry out? Do you change your base layers regularly and rotate them out to dry? Or does moisture just continue to build up?
My own experience confirms that it's better to be damp than to be cold, so I'd never hesitate to fashion a VBL in a pinch, but I'm having a hard time understanding why I'd plan to do things this way, unless there's some technique for getting a chance to dry out periodically.
What am I missing?