As I already said here, if we want to better define our stance on answers in comments, this has to be a community effort. We have to clarify how we react to users posting comments as answers, how, if, and when they should be flagged, and when we want to delete them. I therefore do not think that one meta question suffices to establish a well-rounded policy on this that most of us can get behind. Therefore I will split this process into multiple questions, the first of which is:
Which kinds of answers in comments (if any) do we want to keep?
There are plenty of collections of general arguments against answers in comments. Please have a look at least one of them to make an informed decision:
- Please don't write answers in comments on Interpersonal SE.
- Should users refrain from answers (or partial answers) in comments? on RPG SE.
Post answers outlining a single type of comment that you want to keep. Types can be based on context, e.g., “comments answering questions that were not closed for shopping”. Provide a rationale, with some examples, why these should be allowed. Define your rationale as clearly as possible so we can build a practical policy around this.
Upvote answers you agree with; downvote answers you disagree with.
Answers that have a score of 5 and at least twice as many upvotes as downvotes will be considered community consensus (rule stolen from here). If any other answers have a positive score, we will decide how to proceed on a per-case basis.
Do not post a blanket answer that no answers in comments should be accepted. Such answers will be deleted without warning. The proper way to obtain this outcome is if no answer reaches the threshold for acceptance. (This is to prevent a self-contradictory outcome.) You can post a blanket answer that all answers in comments are fine, but you better have very good arguments.
What this is not about
Whatever the outcome of this question is, it will not be suddenly in effect. We still will have to decide about implementation issues such as:
- How should answers in comments be flagged?
- How should moderators handle these flags?
- How do we react to users answering in the comments?
- How do we deal with old answers in comments?
While it is good to keep such practical concerns in mind when suggesting exceptions, this question is only about setting the goal.