He was one of the original three animators ( along with David Silverman and Bill Kopp ) on The Simpsons ' Tracey Ullman shorts and subsequently directed a number of Simpsons episodes before becoming supervising director at King of the Hill for many years . He was one of the original three animators ( along with David Silverman and Bill Kopp ) on The Simpsons ' Tracey Ullman shorts and subsequently directed a number of The Simpsons episodes ( many of which had John Swartzwelder as an episode writer ) before becoming supervising director at King of the Hill .