As someone who lives in a climate that has real winters (if your highs are above zero you don't have real winter
) turning on defrost does jack crap on a snow-covered windshield. Wipers up allows for easier brushing off of snow, which is the main reason why I put them up at work. Secondary reason being that if they get stuck with ice I can pull them up but then they don't clear as well because the blades are not as clear, and performance becomes poor. And yes, this all done after I've remote started 20 minutes prior