Following "I was too shy to open a beer and masturbate" with "I just grabbed whatever I could and started slicing it" puts Mr. Welch in my pantheon of heroes.
A few summers ago (the really hot one with the 106 degree day) my kitchen cabinet’s frosted glass door did just the same thing. Scared the crap out of me, happened in the middle of the night.
College friend of mine worked summers as a glass tester for PPG (Pittsburg Plate Glass) - lots of protective gear - said some sheets would just explode when he touched them due to internal stresses. Acres of glass in this world - could make a guy paranoid.....
PS - Beer/masterbation - MADE MY DAY!
And I loved this too.