Is really just the difference between a copy editor and a conceptual one. I am currently in Denver at the Mountains and Plains regional trade show. Today there was a panel with Morrow and Houghton Mifflin. Editors from both publishers were there. Both conceptual editors. They are responsible for taking that little bundle of raw material, keeping it absolutely true to the voice of the author, and making sure the ideas and character developments align. They do not edit line for line--they leave that to the copy editors: the folks who rake the whole thing with a fine tooth comb, in the name of one consistent template, namely the Chicago Manual of Style.
And really, if I were to choose I would be probaly go conceptual. Yet, copy editing is absolutely essential to the precision and finesse of a manuscript.
In my own sermon on the mount near the Bodhi tree, I would perhaps call both necessary. And, if I wanted my sermon published, well, I couldn't say one was more important than the other.