Over the years, I’ve worked on a number of publications (training courses, books, etc) that have had copy editors as part of the process. Most were pretty good, and I personally learned a lot about how to write better (my blog could probably use one too!). I’ve always had, as an objective, to give the CE nothing to comment on – but this rarely happened. The Washington Post has a great article, On Copy Editing that explains why copy editors are so valuable. Makes interesting reading.