I know that when I acted in our school musical last Spring, we were not supposed to wear glasses. I had to take my glasses off for all dress rehearsals and performances, and luckily, I am near-sighted, so I could at least see everything that was going on on stage clearly. I think the reasoning was because of the lights. Also, we performed "Titanic", and it was thought that glasses would mess up the costumes and such.
-Lindsey
P.S. The word "specs" reminds me of the car I drive. It is so little, all my friends call it "The Spec".