RORY: No, he didn’t vandalize it. He wrote in the margins, thoughts and stuff.
LORELAI: Like what, like play basketball, eat a sandwich – stuff like that?
RORY: No, stuff, like margin stuff. People like Mark Twain wrote in margins.
LORELAI: Pilot a steamboat, write Huckleberry Finn?
Mark Twain, author of The Adventures of Huckleberry Finn, often mentioned. As a young man, Mark Twain trained to be a pilot on a steamboat on the Mississippi River. His pen name comes from the cry “mark twain”, meaning that the river is twelve foot deep, a safe depth for a steamboat to travel in.
Mark Twain is famed for the barbed comments he wrote in the margins of books he read – his own books, I might add. Saratoga in 1901 by Landon D. Melville seems to have drawn his ire; Twain re-named it Saratoga in 1891, or The Droolings of an Idiot, and wrote in the margin that the author was “little-minded”.
Rory’s comment may suggest that Jess’ scribblings in the margins of Howl were likewise of a sarcastic nature.
The Annotated Gilmore Girls 