Thanks for finding that. It seems the show had random writers that submitted storylines and collected a paycheck. I read that Mike Nichols production company produced the series and was given onscreen credit, but he had no personal involvement in it. David Jacobs was considered the new hot shot writer because of Family and was courted to join Lorimar Productions where he submitted Dallas. Bill Blinn who had created Starsky and Hutch left Spelling/Goldberg productions for Lorimar too and directed Eight Is Enough. Writers for Eight also wrote scripts for The Waltons. I remember seeing an interview with Blinn and he said he never would have cast Dick Van Patten as the father, but Fred Silverman at ABC wanted him because he thought he was funny. The actor Blinn wanted for Tom Bradford was a stage actor and when he came to test, he was a mess on camera. Blinn also went on to say he felt bad years later after the kids turned out to be messes, especially Adam Rich who played little Nicholas and said he would never suggest a child be and actor.
Interestingly, when Jacobs wrote the script for Dallas in 1977, it was originally titled "The Linda Evans Project". In 1981 Spelling would rip off Dallas with Dynasty and cast Evans in the lead.