New authors have fairly weak power. Editors can exert their power to:
- streamline the story such that it flows more smoothly
- cut out dense detailed descriptions that take the reader from the story
- their experience at what it takes to make a book become a bestseller gives them authority
The trick is when the author becomes a proven bestseller, the editor becomes weaker. You can look at the books in a series like Game of Thrones and see how the editor became weaker as the book lengths ballooned.
- A Game of Thrones 726 pages
- A Clash of Kings 761 pages
- A Storm of Swords 973 pages
- A Feast for Crows + A Dance with Dragons 1761 pages
Tom Clancy follows this model as well.