I have seen a few responses on MO that I think are either incorrect or possibly incorrect.
What is the best way to draw attention to possible incorrectness?
(I provide two examples below; if this is poor form, then please edit them out.)
A user posts that it is impossible to prove the Fundamental Theorem of Algebra using the Brouwer Fixed Point Theorem. But another user (disclaimer: me) provides a source purporting to provide such a proof. Due to timing, the former received many up-votes early on; as of this writing, it has twice as many votes at 22 to 11. For both claims, see here. [Added (quid): the answer claiming impossibility was deleted by its owner.]
There is a post claiming that: Most (actually almost all) of ancient Chinese mathematics literatures [sic] are written in the forms of poems. But this claim is unsubstantiated insofar as I can tell, and one might suspect that, e.g., the last example provided is not an instance of an actual poem. Again, this post has garnered many up-votes (15 as of this writing) but I'm not sure how anyone could properly evaluate it without more information or the ability to read Classical Chinese. [Added: An MO user (Marty) posts in the comments there: I asked a colleague -- an expert in Chinese poetry -- about this, and his response is below... "Well the post is fascinating, but completely wrong." etc.]
I can think of a few ways to address such possible incorrectness. One is to leave a comment on the original question or the disputed answer; however, I worry that this method has very low visibility unless it is carried out shortly after the response is posted.
Alternatively, one might edit the post, thereby bumping it up and drawing attention to it, or put up another post disputing the earlier one. But I view such approaches as somewhat aggressive and possibly overkill. (I hope that my examples above are not viewed similarly!)
Yet another route would be to draw attention to the post here in meta.MO. I suppose that is the approach I have taken for the two examples above, but I am curious as to what should be done more generally (if anything at all).
Edit: For a related feature suggestion, Stefan Kohl comments he's left a post here.