I saw that video yesterday - very well presented, I thought. Provides a good explanation of the difficulties of the Hour record whilst simultaneously explaining how the advances made recently have been made (Bradley Wiggins' ability to hold 440W for 1 hour is extraordinary). Boardman's 'Superman' record shows that the aero does make the difference, though; if he could get over 56km with that position, it's clearly worth something. Cycling Weekly had an article recently where they got Graeme Obree into a wind tunnel to test the drag coefficient of the present-day aero position compared with the Superman and Obree's original 'no hands' position - apparently the 'no hands' position is still the most aero available.