I do a different version of rotating. I wait until my rear tire is 2/3-3/4 worn, then I swap them. That way they wear out about the same time and I can order a replacement pair together and save on shipping.

I know Sheldon's idea is to keep the good rubber on the front wheel. However, the tread on a bicycle tire is little more than decoration. Sheldon himself admits that due to the narrow width even a bicycle slick won't hydroplane unless you're going 100+ mph. My method has worked for me for years without issue.