Back before the dawn of time, when I was in school, critiques were the "slash and burn" variety. Or, you could experience its ugly cousin the "death by a thousand suggestions." I've sat through crits where the instructor knocked the bad work to the floor and then walked on it for the rest of the class. Obviously this tended to incite a bit of anxiety.
I've been to several of the festival review sessions that have become such good money makers. Some were useful, others were crushing. But overall, I found that the 20 minute speed-dating method never worked for me. This past year I was fortunate enough to have two gallerists spend a few afternoons with me and really thoughtfully review my work. In this day and age, I completely realize what a gift it was to have that kind of attention - but I think "back in the day" that's how it was done on a regular basis. In both cases, I came away with significant insights that are still guiding the changes I've been making this past year.
I've also had very good experiences with critique groups. For several years I hosted one that met every six weeks at my home. The group started fairly strong...and eventually ended up being a core group of 4-6 people - which actually was a bit of a sweet spot in terms of really having intense time to discuss a body of work. In general, the visual aesthetics and goals of the individuals were fairly similar - I found this helps, having also been a member of a group which had a much different aesthetic...and it never really jelled for me.
Some suggestions for discussing and thinking about your work:
1. Give us some context for the work. Although I like work to grab me, it's also true that people want to do more than just buy an image. They want a sense of the world you're living in. Collectors want to know the background of the artist - who they are and why they're doing what they're doing. This also holds true for fellow artists - giving us a framework helps in terms of deciding what kind of feedback to give.
2. Try to emotionally distance yourself from the project. A good method is to put the work away for a few weeks/months and then come back to it with new eyes.
3. Review it all at once. You've got to find a way to spread it all out. I found this extremely useful when I was editing my book on Val Verde. I went to the Pasadena library, which had these enormous tables and literally laid out the sequence. There were some changes later, but this is where I realized how I wanted to sequence the work.
4. Look for trends. After you've laid it all out, start seeing which pieces seem to fit with the group and which don't. Often it will be your favorite image that doesn't seem to fit with the group...figures, huh? But don't despair, perhaps it was meant to be in a different body of work. Be ruthless with your edit. If there's a question...then you have your answer.
5. Make multiple edits. Consider that you're just looking for maybe 30% of the images to survive the cut
6. If you're working with a group...try not to argue with their feedback...it may not be relevant, it may not be something you want to change...but it's important to understand the impact the work has. This doesn't mean you have to agree - and you can always restate what you're trying to achieve.