The intention might have been different, but the effect is to prevent me from explaining my downvote. Remember: It's not the thought that counts, just the observable effect...

"The point wasn't to prevent explaining why you downvoted" It sort of is. What it wants you to do is to explain how the post can be fixed, not why you do or don't like it.

"The effect is to prevent you from including how you voted" <- well, deleting the answer would also prevent me from indicating how I voted. So would deleting my user... if that's what's desired, it's possible to simple remove the "-1" and leave the rest, explaining why you believe a comment should never indicate how one voted. And this is regardless of my opinion of whether it's a good idea to prevent the indication or not.

@Servy: Well, the current overall effect, when projected onto that axis, is more detrimental than useful IMHO - as even if I've provided an explanation, it is rejected.

@TravisJ: Again, I understand and can sympathize with the motivation and the history, but the bottom line effect is that someone (who's not aware of this history) who's trying to give a meaningful explain of his/her downvote gets told "don't comment on downvotes". Two times out of three they'll just let it go and the explanation is lost.

@TravisJ The "-1" in the post is the only real good heuristic that the system can rely on to determine if a given comment is explaining why someone is downvoting, instead of how the post can/should be improved, but the point remains that we want them to explain how the post can be improved, not why they downvoted. We don't want people to "fix" this by removing the -1, we want them to fix it by focusing on what should be done to improve the post.

TravisJ: Why not just say it outright? "Please rephrase this comment to only include the substantive part rather than mentioning your downvote." and then perhaps some link to the policy, or to the meta.SX question @ale linked to, or whatever.

@TravisJ: It's difficult to try and dumb down my English. But... fine. How about "Please rephrase your comment so that it only refers to the answer rather than mentioning your down-vote." ? Down to 9th grade.

@TravisJ: That does not make it clear that you can't indicate the downvote. It sounds facetious... maybe go the other way: "Since we want XYZ, comments which specifically indicate a downvote are not accepted".

@einpoklum You're trying to write a comment that just gets someone to remove the -1. That's not what we want. If that's all we cared about we'd just strip it off for you. The point is to get the user to re-write the comment such that the whole thing is phrased around how the post can be improved, not why you downvoted the answer. Removing the -1 should be a pretty small part of that.

@Servy : But you have no idea what I put after the -1 !

@einpoklum But we have very good reason to believe that it's an explanation of why you downvoted, and not an explanation of how the post can be improved, because prefixing a post with "-1" is a very strong indication of that. That's why it's important that the message indicate how the comment should be corrected to fix the underlying problems, not the heuristic that we used to try to determine if there are underlying problems.

@Servy: 1. Those two things are often the same, and if they aren't the same, they're usually close enough. 2. The message currently indicates that the comment shouldn't be corrected, but dropped: "Don't comment on your downvote". Correcting a comment you make on your downvote does not make it not-a-comment-on-your-downvote.

@einpoklum No, describing how a post can be improved isn't the same as describing why you've downvoted. The error message specifically says, "If you think this post can be improved, please offer specific guidance." So no, it doesn't just tell you to drop your comment.

@Servy: It doesn't just tell me that, but it: 1. tells me that. 2. does it.

@einpoklum Sure, if you ignore the message, and add in your own message that isn't there, then yeah, it says that, but if you just read the message that is actually there, it's telling you to fix your comment, and how, and if you do that, you can post it. If you're unwilling/unable to correct your comment to follow the guidelines it suggests, then yeah, your only option is to not post it, that's by design. If you can't fix it as you're told to, then, and only then, are you forced to just not post it. Not because of what the message tells you, but because you aren't following directions.

The fact that you need to argue with me to convince me of what you believe the message said itself proves it does not. And your tone, like the message's tone, itself tells the commenter: "We don't want your comment." Well, you got it.