@Phaedrus- I grew up with that acne and chocolate myth, too. I guess I was fortunate, because I never had the severe kind of acne. I saw a lot of other students with the pimples and the pockmarks, though. They suffered a lot of teasing, I remember. We called one guy "Pizza Face" because he had the cystic kind of acne.
My health teacher talked about all the myths about acne, especially the idea that chocolate causes acne. She urged us to wash our faces with soap every day, and she recommended a few creams to try, but she never told us to quit eating chocolate or other candy. She said there was no real connection between chocolate and pimples.