Last month my son calls me in a panic on his cell phone [I'm in a meeting right] and says " dad I'm driving in the rain on 66 and I have the wipers on but I can't see! Because the Windows are all fogged up"! Then I said "do you have the blower set on defrost to blow warm air on the windows?" My son says "yes". Then a few seconds later he says "never mind dad I had the a/c on." And this is from a 26 year old former U.S. Marine with a BS degree in biology...