I could see winterizing with a full tank, if it's a metal tank, to keep it from rusting. But on skis they are plastic, so I run mine low and put stabilezer in it the last day of riding to get the stabilizer through the entire system. During winter I keep all my fuel caps loose so it can breathe.Kind of funny you say that. Your "suppose" to winterize your ski / boat with a full tank.
I've had a similar problem with a tank pressuring and fuel ended up EVERYWHERE