There are many question on meta about plagiarism and I agree it should be addresses in detail inside the FAQ (as pointed out on Plagiarism should be addressed specifically in the FAQ).
Premise
For the problem I'll speak about plagiarism but the feature I'm talking about isn't not intended to limit or to highlight plagiarism. Its intent (of course in my opinion) is to provide a better way to build links within SO.
The problem, part 1
Looking around I found that many (too many) new users don't pay attention to this issue and looking for score they do a quick search and just copy & paste someone else answer (even from SO and sometimes even within the same question!!!) without proper attribution. I'm sure that:
- they don't know it's better to don't duplicate answers;
- it's nice to attribute "honor" to whom first found a solution because this isn't a game but a place to share knowledge.
Moreover I think sometimes (or often) they come to the same solution so it looks like plagiarism but in reality it's not (and this is especially true for short answers).
When I tried to make this clear with someone it's always finished with an escalation, even if I did choose answers unrelated with my own answers, so I don't think it's a really viable solution. No one loves to be named of plagiarism ("...don't you think I'm not professional enough to solve that by myself?...").
The problem, part 2
Sometimes to answer a question you just have to provide few links to other answers (or comments). To write a full answer with links only is not viable (after all link only answers are eligible for deletion) and it'll add more useless and duplicated content to SO. What's then best way to provide a link?
Actual solutions
Often I saw that older and experienced users don't even post an answer for very trivial questions but they just leave a comment (do that, see this, change that) and I think it's a very nice way to help someone else for very localized questions (questions that hopefully will be closed because too localized and maybe even deleted). What makes me very disappointed is to see someone else, see this for an example, (almost always newbie) that uses this comment to post an answer with just some make-up. I don't think to flag for moderator attention is a good idea because:
- after all everything you post on SO is CC-BY-SA (as noted here);
- moderators have a high work load;
- to solve the "problem" they should check, compare, ask and it'll waste even more time but it won't give a reasonable sure answer;
- after all...who really cares?
About problem 2 the only way we can do this is to post a comment (but often it's not visible enough) or to post an answer (but this won't solve the problem 2 because you add more duplicated content and more work for moderators to merge/review/delete).
The new feature
So what, finally, I propose is to add a button to connect answers to other answers and comments (a section accessible with a pop-up, for example, near the answer but separated from comments).
Benefits:
- author, where applicable, will be able to attribute the source (I wrote many times "I don't remember where I saw this solution first time but...");
- other users will see and judge (technically they may downvote, flag to moderators, add comments): more people will judge with the same mechanism used for votes to close;
- who will read that answer in the future will have a more complete view of the topic (because this feature can be used to link related answers too) and this will remove comments made by one link only.