True, the numbers are very small but I still believe that it's for added feel under extreme braking. If you had a see-saw that had 1000kg on one side and 998kg on the other side regardless of how much the total weight was that 2kg WILL make a difference. When stuck out to the side the leg has quite a bit of leverage on the bike. Give it a shot on a mountain bike, if it's noticeable on that (which it certainly is) then wouldn't the best of the best be able to use it as an aid, as tiny as it may be?