My question is related to What should one do when one's question has been answered in the comments? but asked from the commenter point of view.
If you are the user who left the comment and there are no one else who answer it for a while, should you convert your comment to answer - even if the OP does not ask you to do so?
The reason I think this should be the case is that it might best to to keep down unanswered questions to a minimum on the site, especially now math se is now the 2nd biggest stack exchange site.
related: This is perhaps a stupid idea, but I feel even a stupid idea might be worth discussing:
can we consider a new feature to allow comment answers to be accepted or would this be too much hassle?