When a question is closed as a duplicate, it automatically includes a link to the question that it was a duplicate of. In cases where it's closed before it has been answered, this approach makes sense, but what about cases where it generates one or more useful answers before being closed?
In such a case, one (or both) of these two approaches might work better:
Automatically add a link from the old version pointing to the new one: this question has been asked again. In some cases the answers to the newer versions of the question contain more up-to-date examples, and if I'm searching for a question and come across the old version, it would be nice to see these new answers as well. This first solution would be quick to implement and maintain and would make it much easier to find all the answers to a question in one place.
If the two questions truly are duplicates, merge them. That way any future visitor looking for the answer to the question will find all the answers in one place. This second solution would require more ironing out of logistics, such as
- once a question is closed, how long do you wait before merging it? (I think it would be best to wait a week or two.)
- do you use the old phrasing of the question? or the new? or some combination? If a combination, how is that combination agreed upon? (I think it would be best to use the old phrasing and delete the new question. That way, the original poster maintains ownership of his/her question, and later posters are prevented from "stealing" points from earlier posters of the same question.)
To solve the issue of duplicates occurring in multiple locations, a question closed as a duplicate should first gain a link from the old question so that people visiting the old question know to look at the new one for additional answers. The asker of the new question should then have a period of time to edit the question and get it re-opened. If at the end of the period of time, the question hasn't been re-opened, it should be automatically deleted and it's answers should be moved to the duplicate question.
Does this sound like a reasonable idea?