Such things were rather crudely explained to me with the phrase "I've floated a Mersey Trout bigger than that!".Landslide said:Therefore, simply go to the loo before your ride, and you'll be no worse off in terms of total weight (bike+rider).
I think people know if they want a Brooks or not, it's one of those heart not head decisions based on the look and the history rather than the weight.