One of the things everyone in "my" new writers' group agreed on was that we should do critiques. Critiques can be tough--on both parties. In the online writers' group I've been involved with for a few years, we don't do critiques, but sometimes a member will ask on the list for feedback on a piece and then send it by email. I always let people know up front that they shouldn't ask me to critique something unless they're ready to hear the truth.
That seems fairly obvious; you wouldn't think anyone would ask for a critique unless they wanted to hear the truth. What it boils down to, I think, is that people do want the truth...but they want the truth to be positive. I think that most people, when they say, "Be honest," mean it. They think they can take a little criticism amidst the praise for the things they know they've done well. The problem, of course, is that the reviewer doesn't always agree that they've done those things as well as they thought.
Good critiques can be hurtful and require diplomacy, to be sure. On the other hand, a critique that isn't honest or that contrives praise is worthless. I've heard of writers' groups that have guidelines like, "say one positive thing for every negative thing." Forcing balance sends a false message. On the other hand, criticism should be constructive. "This sucks," isn't an especially helpful comment, even if it does. It's hurtful and, more importantly, it offers nothing in the way of direction as to how to create something that doesn't suck.
We talked about this during my first writers' group meeting, but it's a process I haven't dealt with personally in many years. I tend not to ask for critiques, simply to write and submit. I decided that it wouldn't hurt to refresh my memory on what it was like to be on the receiving end, so I posted a short story on a site I know to be frequented by critical and intelligent readers. I chose a short story because I have published very little fiction, and never a short story.
(I do, however, have some of my short fiction on my website at http://www.rockstories.net/id27.htm )
The first response I received called it "mindless mental-floss." Hm. Apparently he missed my memo. He raised a question in my mind, though, about whether I'd effectively communicated what I set out to communicate. I'm waiting to see if others pick it up.
Meanwhile, back to non-fiction.