my prof. lived in germany for a year and I don't doubt he knows a lot about its culture..but he randomly asked my class "how long do germans typically wear underwear?" he than replied after a few guesses and said the general response was a week. now, nothing wrong with that, i go for 3-4 days but it seemed to come from left field (he has a lot of weird facts and figures) sooo, is he just being an oddball or what?