The trick of being a good editor or ghostwriter is to ensure that the final product is professionally written while maintaining the voice of the original author.
Whether I am hired as an editor to go over what is already written or to start from scratch as a blogger or ghostwriter, my goal is to create a final piece that meets the goals of my client and is representative of their personal style.
This is accomplished through phone interviews and/or Skype with the author as well as my 20+ years of writing experience.