"You're the legs of a mother of three"

Sigh - so, a hundred years ago, I was in this one band, right?  When one is in a band, little ruts and quirks and routines of comic effect become de riguer (are you still reading this?  Stop, probably).

In this band, we all got in the habit of doing this:

Band guy 1: "Oh!  I'm gonna buy some Oreos."

Band guy 2: "YOU'RE some Oreos."

Or:

Band guy 1: "Did you see they finally painted over that dumb graffiti that said 'Society is a carnivorous flower'?"

Band guy 2: "YOU'RE a carnivorous flower."

I think you're getting the idea.

So, one night, while we were all watching Goodfellas, some band member, vis a vis a strewn-about Lorraine Bracco, wistfully spouted the fateful words: "Those are not the legs of a mother of three."

I think you can figure out what happened.