Force comments to chat if the author already posted n comments or is replying to such a comment. This should considerably reduce moderation load of long comment threads.
Automatically force comments to chat in the following cases:
Somebody who is not the post’s author and who has already posted n comments on the post makes another comment. This shall include any deleted comments, except self-deleted comments or comments that were flagged obsolete and deleted (presuming a separate obsolete flag). Exclude any comments made from review or by diamond moderators.
Somebody posts a comment that @-pings a user to whom the above criteria apply (has already posted n comments on this post; not the post’s author). This includes if the new comment’s author is the post’s author.
With forcing to chat, I mean:
Instead of the intended comment, leave a comment by the Community user indicating that the discussion has been moved to chat. If the new comment contains an @-ping, let the community user use it.
Do not tell the user that their comments would be moved to chat.
Copy all existing, undeleted comments to chat (except those by Community).
Move the new comment to chat. If it’s heuristically part of a multi-part comment, move the other parts as well.
Make the new chatroom the target for all further comments moved from the post (be it by the proposed mechanism or moderators).
Do not block comments that do not match the above criteria.
One of the reasons why we move comments to chat is to make room for (existing or future) relevant comments that would otherwise get buried under irrelevant ones or long discussions that hardly anybody is willing to read. Separating the wheat from the chaff here is very tedious for moderators and one of the major sources of disputes when moving to chat. Therefore it would be helpful to partially automatise this: Moderators waste time on this, are inevitably slightly biased, and are perceived as strongly biased by some users.
Now, the above certainly doesn’t completely automatise everything, but it should apply to quite a lot of cases and have a low number of false positives, i.e., relevant comments forced to chat. If a user has something relevant to comment, they will almost certainly do it in their first few comments. Later comments are very likely to be:
- part of a back and forth (a.k.a. discussion) that has a good chance of continuing for quite some time,
- answers in comments, be it as comments on a question or opposing another answer.
Intensive back-and-forths often start with relevant comments and slowly degrade in quality over time, which makes it difficult to draw the line of the last comment that is not moved to chat. Since every party in the discussion want to be the one to have this last word, this is also a source of disputes. Therefore having an automated decision here is particularly valuable to moderation.
Tuning the Criteria
I would suggest n = 3 for most sites for now (on metas, it should probably be higher). One might consider adding a criterion of a minimum number of comments on the post.
With some data crunching, it should be easy to find a good value for the parameters: Just look at all cases where moderators moved comments to chat, deleting most, but leaving at least one standing (or undeleted shortly afterwards). Then determine how many of these comments would have been caught by the proposed criteria depending on the parameters.
All of this is written mostly based on my experience from moderating a comment-heavy site (Academia). It may not translate well to some sites, though I don’t see why. Anyway, I am aware that long comment discussions are hardly an issue on many sites.
“Doesn’t this kill even more discussions?” – Please see my answer here. Briefly: I am not sure whether killing discussions by moving to chat is a “bug”. Moreover, it may even be that moving discussions to chat earlier is beneficial to their continuation.
It may be possible for users to exploit the mechanisms to intentionally get the last word in a discussion, by intentionally not pinging their opponent. However, this is already possible to some extent today: If you do not ping your opponent, there is a considerable chance that they never look at the comment thread in question again and thus do not respond.