To reduce the number of comments and follow up questions that get posted as answers, I suggest a "question detection" feature be added to the answer box. This would be somewhat similar to the subjective question detection. It could look for the following words (give or take):
- ? [question mark] (except in code of course)
It would simply display a warning saying "If you want to post a followup questions, please use the Add Comment button and post a comment instead." Perhaps this would only apply to users with < 200 or so rep.
Yes, this is imperfect. With any luck, though, it would reduce the number of non-answers posted by newer users.
I agree with the posters who have noted how annoying this would be. It might be less annoying if it applies only to low rep users. Or perhaps there's a better solution flat out. The real core problem is that new users are being downvoted and scolded when they post followups as answers (SO is not a forum, but it sure does look like one!). If we can't have a way to prevent this behavior, maybe we just need to be a little more gentle.