Here's the 5 OU coaches who did not have a winning record while there.
John Blake 12-22 1996-1998
Howard Schnellenberger 5-5-1 1995
Gomer Jones 9-11-1 1964-1965
Lewis Hardidge 11-12-4 1932-1934
John A. Harts 0-1 1895
Now for my Paul Harvey rest of the story.
John A. Harts was a student and elocution teacher at OU and was the primary organizer of the first football team at OU that started playing in 1895. The team was made up of students and Norman, OK residents and only played one game that year. They lost to Oklahoma City High School 34-0 and did not make a first down. Yes, you read that right. They lost to a high school and did not make a first down. John A. left OU the next year to go prospect for gold in the Artic at the ripe old age of 23.