Don't feel bad about not getting that reference in ASND – I didn't catch it either, and I'm usually the first to do so. I'm curious, what version of the play was the book referring to? The only one I've seen is the Marlon Brando movie, and if I recall correctly, they cut out that part. It was in my high school acting class, and when we saw the movie, our teacher made us read the play as well. No one even paused over it until our teacher "clued us in."