Asking for feedback on your writing is kind of like chucking a boomerang: It tends to come back to you. The person taking the red pen to your work may soon ask for the same treatment in return. How can you hone his efforts and still have him speak to you the next day? Here are some simple suggestions.
When you receive someone's writing, don't let dust gather. Proofees hate to wait, even those who don't think their pens are filled with gold, and you can't exactly blame them. Soliciting criticism involves trust, a lot of trust. If days roll into weeks with no word from you, your proofee may not only think you prefer clipping your cuticles or mining for earwax to looking at his stuff, he may also conclude that his trust was misplaced. Don't hand him an excuse to ignore your edits -- read it now. (A related note: It isn't smart to pass a project of your own to a proofee you're keeping waiting. Therein lieth trouble.)
Once into the work of it, remember that concise feedback is a virtue. Limit the scope of your critique, no matter the state of the story. Allow me an illustration. Image that a relationally challenged friend stops by your place for coffee. He drops his 350 pounds onto your futon. You notice that he has buttoned his Hawaiian shirt (the one with the magenta parrots) crookedly. His toupée lolls on his skull. The acne speckling his cheeks glows bright as a stop light. And his snaggletoothed smile? It reminds you of a bad split at a bowling alley. "Women just don't like me," he complains, "and I don't understand why." Now, you could laundry list each thing that's preventing him from becoming Casanova, just as you can pick over every misplaced comma in a draft. But voluminous critiques often outlast their receivers' attention and patience. Even if a story is hopelessly broken, focus on two or three of the big structural issues and a handful of the worst grammatical mistakes. Who knows? Maybe the proofee will take your counsel to heart and, with practice, eventually write something that becomes the envy of everyone.
If practice is -- as some authors maintain -- the key ingredient in writerly success, then watch your tone. Feel free to let your proofee know exactly what works and what doesn't. But don't say that the monster appearing in the finale is about as ferocious as an arthritic My Little Pony. Don't sniff that a turnip has more sex appeal than the shirtless corsair who's supposed to sweep the heroine off her feet. And don't scoff that the mystery is so simple your four-year-old nephew could figure it out from page one. Even if such things are true, your wit will do more to discourage future efforts than improve present ones. If offenses must come, let them do so through what you say, not how you say it.
(Picture: CC 2006 by altemark)