I wear glasses (don't have contacts) and have tried different things to see if it makes me a better player or not.
Glasses on or glasses off, drinking or not drinking, having only 5 beers instead of 6, wearing my ugly shirt or my favorite shirt, eating before or after the tournament, wearing underwear or going commando...none of it seemed to make any difference. I'm just mediocre at playing pinball and I've come to accept it.