One of our former fearless leaders had a mantra of "be bold". If there's something you're unsure about, feel free to ask. Generally speaking, good-faith edits are okay. If you do something awful, we can always revert the page. :-)
If someone's available in IRC, that's a quick way to get feedback on a change you're unsure about. If it's something more substantial or if no one's around, discussion on the mailing list is probably best.
Happy docs-ing! BC