it was my impression that Cybil Sheppard's ego was very much present, and definitely not much help, but not the source of all that went wrong.

Glenn Gordon Caron, the showrunner, was pretty new at the showrunning thing, and full of ideas, obviously good ones, but not only. And a perfectionist, and had to have perfect scripts. WHich wouldn't be bad, if they weren't late all the time. the whole production stood and waited for him to finish scripts, and then scramble to film and edit and send off in time to air. Which just wasn't sustainable long-term. Even with cocaine (especially with cocaine? not sure). It felt like a good Greek Tragedy overall, with tv series being doomed exactly by what made them so good. I really need to write that post...