Excerpts from a message I received about Joan Rivers…
I've always wondered how different her career might've been had she turned down Fox's offer for her own talk show in the 80s, had she stayed Johnny Carson's permanent guest host. Might Johnny have retired earlier and Joan would've eventually become the star of The Tonight Show?
My understanding is that the reason Joan grabbed the offer from Fox was that she'd come to realize she didn't have much of a future on The Tonight Show. Ms. Rivers had lost Johnny's seal of approval. Ratings on the nights she filled in for him were down but someone on her behalf was leaking cherry-picked numbers to the press that made it sound like she had more viewers than Johnny. (A rumor made the rounds that execs at Fox had been fooled by those releases and that's why they made their offer to her. I don't think I believe that.)
Johnny, I heard, was not happy with how Joan was doing his show, getting some guests upset with things she said or asked, and refusing to limit the amount of time she spent plugging her other enterprises. Given that and descending ratings, I don't think she was destined to remain as guest host for long. And I can't imagine that getting the permanent job — or impacting when Johnny decided to pack it in — were at all in the cards.