This is not a feature-request, just a suggestion for discussion.
Lately I was surprised with the great number of "late answers" which were either not answers, answers with just a link, or simple and small answers under questions with good, up-voted, and accepted answers.
I am guessing from what I have read so far, that about 80% of these answers do not add or bring anything new to the existing accepted answer. Most of the time these answers will remain on the question with no up-votes and probably no down-votes either.
Would it be a good idea to implement a second moderation on "late answers" by experienced users (with badges) on the tags to which the questions belong?
For example, new answers to a question with an accepted answer more than one year old would be peer reviewed (this would be a second filter) by users with a minimum number of reputation and badges on the tag. If both reviewers think the answer does not add anything to the accepted answer, it can be removed.
It would work as second "late answer" queue, that would receive answers filtered from the already existing one. By filtered I mean: with no "not an answer" answers, and with comments, and up-votes or down-votes from the broader first queue.
- More work for SO's developers and experienced users;
- Discourages new users from participating on SO (this is not good, but..);
- Helps SO to keep itself organized;
- Encourages more high quality "late answers";
- Encourages "late answers" on questions with no accepted answer.
I am not sure if this suggestion affects SO's democracy policy (if it does, then this suggestion is a bad idea), but thinking long-term, SO will need a leap of improvement toward this kind of organization.