Is direct criticism of another answer in your own answer ok?

Question

This is a question about etiquette and manners.

If you are answering or have answered a question and you disagree with something written in another answer, would you think it was ok to directly criticise that other answer in your own? For example, by editing your answer to include something like this:

"ProfRob's answer doesn't add much. In his answer he says x, y and z but I think he is wrong because of alpha, and beta."

Or, do you think that you should, at least initially, raise that objection as a comment on that answer, maybe with a downvote if you feel strongly, so that the other author knows they are being criticised and might perhaps resolve a misunderstanding or make a correction?

I would say the latter. I think whether the criticism is justified or not, some courtesy might be expected.

My problem with the former approach is that at best, it seems discourteous and will likely lead to an extended "exchange of views", and at worst it denies the right to respond if the other author is unaware of the edits being made in another answer.

Related: Proper procedure for addressing an incorrect accepted answer

Answer 1

There are many posts on this site where users write something along the lines of "this extends SoAndSo's answer" or "this complements SoAndSo's answer," so it seems reasonable that something along the lines of "this contradicts SoAndSo's answer" would also be acceptable.

I'm also of the opinion that the wording probably matters. For instance, I think "doesn't add much" that you wrote is probably a bit unnecessarily harsh. It would be better to identify where or why they went wrong, for example: "SoAndSo assumed Scenario X, but that doesn't hold here because of Y".

As to the comment and/or downvote side, I believe that at least a comment is warranted in this case. It could be something as minimal as, "Hey, I've pointed out why this answer is wrong in my answer." or, if it fits within the 600 characters, you can identify the problem in the comment, "You seem to be assuming X, but that doesn't hold here."
Whether you want to downvote it or not is up to you, but I've frequently argued that we should downvote bad/wrong answers as we see them.

Answer 2

Is direct criticism of another answer in your own answer ok?

I think such references should be avoided (and are often annoying to me). They should be avoided for the same reasons that any distraction inserted into an answer should be avoided. I don't think there is any upside that outweighs the downside.

For example, if I say that Kyle_Kanos's answer "doesn't add much," this distracts from my own answer, since the reader probably wants to jump up (or down) to Kyle's answer and try to figure out just why I think it doesn't add much. In this sense, references to other answers are kind of like footnotes--they are a distraction from the main text.

Also, such references almost necessarily introduce data that can go stale, such as references to usernames, which can be changed. This issue can also be a privacy issue, such as the situation where a contributor wishes their previous username to be forgotten, but that username has been hard-coded into a comment or an answer.

Further, an answer should be reasonably self-contained. This is also the reason we avoid link-only answers. An answer that references some other answer becomes at least partially reliant on that answer sticking around, not being edited, not being deleted, etc.

My recommendation would be: Just put your head down and write your own answer as clearly and independently as possible. Then use comments, votes, and suggested edits to critique other answers.

Answer 3

Generally, when you post an answer with other answers already existing, you will have something to add to the other answers or take a different point of view that may contradict them (after all, there is no point in merely repeating already existing answers). In this case you should bring your own answer into context with the other ones in order to show that your answer is an informed one that does not ignore the other answers. After all, it is only discourse that drives science.

As for the question whether you should contact the authors of other answers about the criticism you raised: the purpose of SE is to answer the question asked by the OP, not to directly get into contact with the authors of other answers. When I criticise other answers in my own answer, then only as an obligation against the OP. I don't feel I have a commitment against the authors of the other answers.