I'm not sure I've met any, but if I extrapolate from the blue-collar folks I was exposed to I'd think it might be hard to tell. Anecdotally, of course... You'

I'm not sure I've met any, but if I extrapolate from the blue-collar folks I was exposed to I'd think it might be hard to tell. Anecdotally, of course... You've probably heard of high-functioning alcoholics, it's entirely possible to a high-functioning crackhead as well - at least for a while. I expect the point of exposure for most people comes not through continued use, but the point when something interrupts their supply. That's where they end up crushingly depressed, violently angry and indebted in ways that will surely screw-up the rest of their previously well-functioning life.