Famous for being reclusive, he has steadfastly refused to participate in any commentary for the Simpsons DVDs.
Used to write all his scripts in a coffee shop. When smoking was banned in that coffee shop he bought the booth where he used to sit in and moved the whole thing to his home.
He used to be a fixture in the writer's room of The Simpsons (1989), but ceased coming in when smoking was banned in the writer's room and thereafter submitted his scripts by driving up and handing them in from his car window.
His animated likeness, though not his voice, has been featured in over nine episodes of The Simpsons (1989). Pedestrian viewers often mistakenly think that the likeness is meant to be David Crosby.
He is wildly regarded as one of the best comedy writers of all time.