User blog comment:BertH/Anonymous editing and your community/@comment-25223755-20150729105452

I'm in favor of having the option, even though I think most wikias shouldn't use it. Some forums will tend to attract trouble, and others may need to fend off a temporary flood of vandalism or spam. A few may require higher standards for expertise or group membership. I also think it should be possible to separately anon-block different channels: Page edits, comments/talk pages, forums. (Not PMs, because that includes "emergency" communications.)  There's also the issue that some users can't register easily -- I myself had to go to Contact: to get my email address verified.

Over at Thaumcraft Wiki, what I'm seeing is that the anonymous editors are split more-or-less evenly between well-meaning edits and graffiti or petty damage. Making things trickier, some of the well-meaning editors (and not just anonymous) are dubiously literate, while much of the petty damage seems accidental:  "whoops, stumbled into edit mode". I try to recognize these distinctions in my response:  apparently accidental stuff gets reverted without heat, while the "p*nis & poop" edits get reverted with a 1 or 3 day block on the IP. For poorly literate edits, I try to fix them while keeping any useful information they were trying to add, by way of encouragement.

For the comment threads, I often tell constructive IP's, "hey, maybe you should make an account", especially if I spot a regular contributor. Sometimes they do, and we've been getting more named editors lately. (Yay!)  Comments also offer a few abusive comments such as "you idiot..." or worse, but those went way down when I started deleting the prior examples. Which brings up another point:  The "broken windows" idea definitely applies to wikis, people contribute in the same vein as what they see on the site.