How valuable are editors to experienced writers like Phillip Pullman?

No, I've been writing for 30 odd years — and um it's has I wouldn't say it's been a wrench saying goodbye to it, but it was the definite feeling of well here we are. Goodbye. You're on your own now. Best of luck. — Can you remember the last day that you actually finished writing tinkering? What that felt like? — Uh yeah, relief because you know it's 30 years. — Yeah. — I finished it must have been eight times. Eight or nine times. And my editor, who is very good and who has been saying this to me for 30 years, longer than that, 40 years. This ending is terrible. — What? — It's no good at all. Go back and do it again. — No. — Yes, he did. Um he This is why I value his advice because he's always right, bugger. And um I have to go back and rewrite it, which I did, and it's much better as a result. — Really? — Well, he's a very good editor. You know, he sees what works and what doesn't work.