When I tell people that I’m a freelance editor (including other writers), they instantly assume that I’m a copyeditor, with a keen interest in working on the grammar and punctuation of my clients. I’m not surprised that writers often jump to that conclusion. Majority of editors that I encounter actually ARE copyeditors. However, what is the point behind looking at the appropriateness of a given word in a sentence when on page 152 the bad guys are setting up the bomb that will level the city, and the good guys find the bomb and disarm it by the end of page 154.
This may sound incredibly odd coming from a professional editor, but in all honesty, grammar takes a backseat to story and character.