I think that it all depends on the experience of the rider involved.
BITD, if you put Whopper, Diggens, Lynch on their normal race bike and me on my normal race bike, they would beat me 60% of the time. Put them on a Piranah (sp) or Burner and me on my normal race bike, then they wouldn't beat me ever. However, I think when you are at the top in racing, it makes no difference if a bike has aero tubing or normal tubing, as long as it is a quality race bike then that is all that matters.
Back to these days and put Dale Holmes on any bike in the world and he will beat me.... Everytime. But then Dale is a great racer and I am a fat bald bloke