As jrg♦ said (pinned in main chat):
Hey folks who use "canned" comments: If you see one thats already there that expresses the same general idea, don't add another one. Thanks. :)
This has been happening a lot lately, and I'm pretty sure it's mainly because many people are not using the new review system in an entirely correct manner.
Short Version
If an appropriate comment (canned or not) has already been posted, don't add another one that says the same thing, even when reviewing low quality posts. If no (additional) comment is needed, use the "No comment needed" option.
If you see a duplicate comment--a comment that says the same thing as a previous comment, either in the same words or different words--flag the comment.
While it's not appropriate to post a duplicate comment, you can upvote the comment you agree with. That's one of the big reasons comments can be upvoted--to prevent unnecessary additional comments from existing.
Full Explanation
As an overview of how canned comments work, note that there are two main ways that comments get posted (semi-)automatically. Both are very good things...when used properly.
- The pro-forma comments userscript. (See this meta post for more information.)
- The new review system for low quality posts offers a Recommend Deletion button. (If you have enough reputation to cast delete votes on answers, it's a Delete button instead.) When you click this button, you are presented with the ability to post one of several pre-written comments, or no comment at all.
When we close posts, we choose a close reason. When we flag posts, we choose a flag reason. But choosing a comment when recommending deletion in review is not like that. Unfortunately, many users seem unaware that not posting a comment is often the proper choice. Consider:
Choosing to post a comment when recommending deletion doesn't do anything besides posting the comment. It is not a way of voting on what is wrong with the post. There is no counter that gets incremented every time someone posts (for example) the This is a comment, not an answer comment. Those comments just accumulate needlessly, take up users' and moderators time as they are flagged and removed, and distract from any potentially valuable subsequent comments on the same post.
It is OK to not post a comment when recommending deletion. That's why not posting any comment is the first option in the list of what to do.
If the comment you're about to post has already been posted, or something like it has been posted, don't post your comment. This is true even if the comment you're about to post is manually composed, or if it's a different kind of canned comment (i.e., a "pro-forma" comment).
If a comment has been posted addressing what's wrong with the post and you agree with it, consider upvoting the comment. Comments can be upvoted, and we get to upvote up to 30 comments per day.
A comment with upvotes sends the message that it's supported by the community. In contrast, multiple comments saying the same thing sends the message that the the post was reviewed by people who weren't paying close enough attention to notice that what they're saying has already been said (whether or not that message is accurate).
If you somehow manage to run out of comment upvotes (this has happened to me occasionally), however, you should still not post duplicate comments.
When reviewing "low quality posts," remember that you can post your own comments, and do not have to use the canned comments provided in the deletion dialog. If no one has posted a comment explaining what's wrong with a post, and none of the comments in the deletion dialog is exactly right for it, post your own comment instead.
However, if your own comment says essentially the same thing as something that's already been said, it is almost never appropriate for you to post it.
Furthermore, the canned comments often do say exactly the right thing; they cover some of the most common problems with sub-par posts.
Sometimes you might find your own canned comments (i.e., through the pro-forma comment user script) to be better than the comments offered in the deletion dialog. Unfortunately the pro-forma user script doesn't support review, but that's not a big problem. You can open the post up in a new tab/window, and post the appropriate pro-forma comment.
However, that you're using your own customized pro-forma comments doesn't mean you should post a comment that says essentially the same thing as one that's already been posted.
Those guidelines should, hopefully, help clarify the full range of options that exist when reviewing low-quality posts.
If you don't see a lot of duplicate comments and are wondering if this is really a problem, the reason you're not seeing them is that many of them have already been flagged, and/or removed by moderators.
If you do see duplicate comments--which means comments conveying the same information, not just comments that have exactly the same wording--flag the duplicate (i.e., the second one). Or duplicates--unfortunately, a comment is often duplicated more than once.
- I've flagged lots of these comments, and the vast majority--or all--of my flags have been approved and the comments removed. (I can't state with certainty that it's 100% since I have a small number of rejected comment flags, but I strongly suspect those rejected flags were unrelated flags, not flags on duplicate comments.)
- I've been using custom flags to point out duplicate comments, because just by looking at a duplicate comment by itself, it might not be clear why it ought to be removed. No one has criticized me for this practice, but I'm not sure it's the best way; maybe flagging as not constructive would be preferable. Perhaps a moderator can weigh in on this.
- It might feel unclear which of the duplicate comments should be kept (if they are worded differently). So I used to flag the post itself and explain this. But then a moderator told me in chat that I should instead flag one of the comments (presumably the second one). So as I understand it, that's what we're supposed to do in that situation.
