I was checking Joshua Kosman's blog to see if he'd posted anything lately (alas, he has not), and I was stumped by the phrase "the tentative Alphonse-and-Gaston footwork between Nelsons and the string players " in his entry about hearing the BSO perform Mahler's Ninth.
So, off to Wikipedia, where I learned that Alphonse and Gaston were comic strip characters from the early 1900s known for out-politing each other. It says the catchphrase "After you, my dear Alphonse" is often used "in situations when a person receives a dare to do something difficult or dangerous or both; the catchphrase returns the dare to the person who made it."
Delightful. I love learning about cultural creations like this, from people like Kosman with wide-ranging interests.