Recall the basic law of medicine: First, do no harm. Would that editors obeyed that same dictum.
Editing and writing are complimentary skill sets, but they’re not interchangeable. Some very, very good writers couldn’t edit their way out of a dangling participle, and some top-notch editors lack the smidgeon of stylistic creativity that lets them advance beyond a dark and stormy night of writing.
Editors must do a few things, and do them well.
First, they must guarantee that the language “works.” Usually this task entails correcting sundry grammatical and usage errors — but really, the goal is to preserve the flow of the language even if some errors pass unretouched. Writing remains the ultimate form of communication, so the very best writers and editors make sure that the intended message is communicated; obsessing about words and sentences has its place but this place is always subordinate to clarity of communication for the widest possible audience. Remember: Hypercorrect prose can alienate readers more than prose that contains a few minor rhetorical liberties.
Second, a superior editor inflicts minimal violence to the natural style of the writer. Some writers prefer complex sentences; others use various parentheticals like they’re paid by the dash. A good editor will massage the language while granting privilege to the writer’s style — not the editor’s. Unless you’re working with a clearly substandard writer, a light touch is best.
Third, editors must guarantee the factual accuracy of what’s written. For fiction editors, fact-checking may be nothing more strenuous than noting continuity errors in the plot or identifying technical errors like omitting certain speech tags in a dialogue-heavy section. For non-fiction editors, fact-checking requires research: Not just verifying that some other (usually, online) source corroborates, but that an authoritative source that’s as close as possible to the original fact corroborates, that math works, that arguments are formally valid, that all reasonable perspectives are respected and that attribution rules are carefully honored.
Fourth, editors must coach writers in a manner that provides value without condescension. Don’t offer blanket praise for mediocre writing but instead identify tendencies that affect the quality of the prose and provide specific and concrete suggestions for correcting them (e.g., don’t say, “this doesn’t flow well” but rather identify the discontinuity and offer a suggested revision). If a writer tries to B.S. the facts, call him out — vigorously. Or if a writer hits a home run, take the time to thank him for it.
Of course, there are some things a good editor won’t do. For example, he won’t consider himself a co-author and take liberties to rewrite major passages in his own style. He won’t presume to elevate disagreements about style — like the use of literary devices including metaphors and rhetorical questions – into Commands From On High. He won’t just assume that the writer’s an expert and therefore no fact-checking is necessary, nor that the writer is an idiot who’s incapable of getting it right without the editor’s guidance. He won’t offer unwarranted praise nor will he pick trivial nits just to appear like he’s paying attention.
Editing requires superior knowlege about English syntax and style, painstaking attention to detail and a disposition that favors a light touch over “I’m the editor” authoritarianism. Good editors are people persons, equally capable of coaching hesitant new writers as established writers whose self-importance may outweigh their native skill.
Above all, good editors do no harm.