I've seen countless comments on Biostars in the vein of:
Please leave this as a comment on the answer to your question instead of a new answer to your question.
How difficult would it be to provide a mechanism for Biostars moderators to move a user's inappropriately placed answer as a comment to the appropriate answer? Is this something that is on the development roadmap? Is there a development roadmap? If not, would our time be better spent developing an interface to reduce the need for this type of passive moderation?
This is an important issue that has come up before. Changes have been made to help, but I continually see this happen. Unfortunately I see this a lot in new users who post additional information as an answer -- and I see this as a problem because some people may avoid looking at a question if they think it is already answered and some new user questions go unanswered.