a black mans performance would be down IF the same skin area was involved- but due to the cm2 of skin on a black mans shlong being at least 208% more than the equivalent Caucasian's, then performance should theoretically be greater by 64%. but that needs to be tempered with the resulting heat from the thrusting friction- a smaller 'piston' can pump faster due to weight/ opposing movement ratio. so a white mans performance would be down a further 8% due to friction, which a black man wouldnt be hindered by as much. so if you are white, I recommend you have your girl drink a bottle of slick 50.