I say that’s mostly right. Plot advancement is a crucial gauge for keep-it-or-chuck-it choices. Just don’t let good intentions regarding plot advancement take you on some joke-axing rampage that squelches your humor in service of brevity and focus. As with all things writing, revising humor is about finding balance. A joke that doesn’t directly advance the plot can stay if it’s organic to the story, evolving from the character or situation. That contributes to the personality of the project, which is essential, too. Be tough with these criteria. The jokes that don’t pass the test with room to spare—the funny-for-funny’s-sake gags—should get the ax.