These are some different types of reviews:

- Line edits. These pick out individual lines and say what is good or bad about them. Lists of grammatical errors are line edits.

- Story theory reviews. These compare a story to some theory about how stories work, or how this type of story works. Anyone who cites Joseph Campbell or talks about theme is doing a theory review. This is the kind of review I usually write.

- Style and technique reviews. These are the reviews that say "Show, don't tell," or, "Pacing is slow in scene three."

- Reader reviews. Say what you liked and didn't like, how you felt and what you thought while reading the story, and what it meant to you.

If you're a good writer, do whatever you want. If you're not confident about your writing skills, but you know that a participial phrase should be set off with a comma, feel free to talk about grammar. And if you don't know what the hell you're doing, write a reader review.

You may do a grammar/spellcheck review if the story's already been added to the group, but don't add a story to do a review that's only grammar and spelling corrections. If the only review by the group only corrects mistakes, it makes it look like the group is seeking out bad stories.

All types of reviews are valuable. Personally, as a writer, I want reader reviews. A single spot-on theory review can be incredibly valuable, but I can get all the other types of reviews from writers' groups and from my pre-readers. The main reason I started writing fan-fiction is to get opinions from readers--from people who don't think like writers--about what they liked, what they didn't like, what they thought a story meant, and which parts bored them. Those are the most important things to me! And anybody can write that.

I can still mix and match, right, just as long as it's not jarring (don't drop a grammar level analysis in the middle of a theory analysis).

Structure is boring - perhaps I'll start off with a style and integrate it into theme, sometimes the writer part of my brain is offline, sometimes there's too much caffine in my bloodstream to notice anything but grammatical issues.

Heck, my current editing/prereading work usually starts off with a high level review of the chapter before jumping into line by line.

Interesting, I'll definitely take this to heart. This'll help me organize my reviews a lot.

521637 Ah, this is exactly what I wanted; and you're enforcing rules retroactively? That's wonderful! I love capriciousness!

Note that, 'how a story should work' is the sort of thing a style review should address.