Mark Twain did it. So sure you can wear white all year. However, people who do so unaware of the conventions usually stand out like sore thumbs. The rule was created to "protect" them as much as anything. You just have to think about all the variables in creating your fit so that you make it look right and so that you feel comfortable in it. Even if you're an absolute master of the casual, you'll be seen as making a statement, which is fine with me. Most of my winter whites are dressy clothes -- wool trousers, French corduroy suits. white wool windbreakers -- but at the other end of the style spectrum, white jeans especially and trousers are being shown in top New York fashion windows this season, so we'll see where it goes. Call it global warming of sartorial conventions.