This is a good explanation of apparent wind - a concept that boggled my mind until I had a good few years of sailing under my belt. http://www.youtube.com/watch?v=8xo0ySZ98oc The idea now fuels my quest for speed in windsurfing. 29.85 knots PB

The key ingredient that you are missing here is that the advocates are agreeing to increase the result of an emissions calculation by including the power plant emissions.