The joke-teller's memory problem

In today's New York Times, science writer Natalie Angier probes the problem faced by many a speaker, impromptu or planned: Why can't you remember jokes when you need to retell them? She starts with what our brains can remember: patterns, as in music. From the article:

“The brain has a strong propensity to organize information and perception in patterns, and music plays into that inclination,” said Michael Thaut, a professor of music and neuroscience at Colorado State University. “From an acoustical perspective, music is an overstructured language, which the brain invented and which the brain loves to hear.” A simple melody with a simple rhythm and repetition can be a tremendous mnemonic device....when the alphabet is set to the tune of the ABC song with its four melodic phrases, preschoolers can learn it with ease.

But when it comes to jokes, based on surprise, the factors that make 'em laugh also make the joke itself harder to remember. The key? If you're going to use a joke, you need to practice it again and again and again to ensure you'll recall all the details that make it sing.