Let's imagine this scenario:
- User 1 asks question A
- User 2 asks question B -- related to question A, but not a duplicate.
- Question A gets answered, the answer is upvoted and accepted, then user 2 notices the answer to question A would be the perfect answer to his question B.
How should user2 proceed here? Post a comment to his own question with a link to question A's answer? Copy the entire answer and re-post it as an answer to his question? Post a new answer being it just a link to the original answer? Delete his own question, even it not being exactly a duplicate?