If that's how you learn best, MAYBE not. There are classes where tests are heavily based on what the professor says and he/she might not include a lot of the info on the powerpoints. How would you deal with that? UD classes and med school classes are going to have tons of info thrown at you. Will attending the class once help you remember that information?
edit: Actually from what I hear, you learn a lot on your own in med school. If so, I still think taking notes for yourself while reading over things is a good idea.