TAYLOR: You weren’t invited because we are dealing with the Jess situation.
LUKE: The Jess situation?
LORELAI: Uh oh. If this was the Wild West, we’d be pushing the horse aside and diving into the water trough right about now.
A trope in Western films, especially in comedy or parody versions – during a gun battle, those who are unarmed or incapable of fighting will dive into a nearby water trough to escape injury or death. Lorelai sees Taylor and Luke as the gunslingers, while they are the innocent bystanders.