there is truth to the myth...

there's a coating on the outside of lightbulbs that disipate the heat faster. when you touch the lightbulb with your hands/fingers you rub this coating off. it doesn't affect the light bulb strength, or the kelvin of light that comes out of it. all it does is prolongs the life of the bulb..

as for cleaning the bulb? i imagine if you got shammy of some sort... a really soft cloth used for waxing a car or something...personally... i man handle my bulbs.. when they go out, i buy new ones...