I have noticed that many inexperienced SO users tend to reply to answers by creating an answer rather than via a comment or an update to their original question. The problems this causes are:
- The new "answer" will not make sense if it is re-ordered away from the answer it is responding to.
- Even if order is maintained readers then have to piece together a disjointed set of answer/response posts which can get confusing.
- Genuine answers get less screen estate.
This happens a lot and currently relies on flagging and editing by the community to resolve which generates a lot of overhead.
I suggest that if a user answers their own question they should be re-directed to a page which asks "are you sure this is the solution to your question?", and if not then prompts them to either comment on another answer or to append to/clarify their original question.