A good editor will also go beyond spotting and fixing technical problems in the text. He or she should be able to appreciate, respect, and harmonize the author’s intentions and the publisher’s or reader’s requirements. Above all, he or she should give the text the attention it deserves—to polish the draft to its finest form, clearing it of all roughnesses and infelicities, so that reading the text becomes a pleasure rather than a chore or a conundrum.
-- Jose 'Butch' Dalisay Jr., “Editing as a profession,” in yesterday's Philippine Star
PLUS: Reposting--my own process of editing Dear Migs, the MGG book