Flagging late answers is only soo much fun (40+ today were the not-an-answer variant with a couple of cool-thanks).
How about trying to prevent them, at least from new users? Something like an inverse flag dialog which opens after they typed the answer and click on post-answer:
Thanks ... [blah blah] ... Please take a second to categorize the intention of your answer and check one or more of the following: it is
- a complete/partial answer to the original question
- a link to an article/tutorial/product and a short synopsis as to why it's helpful
- a link without synopsis
- a question related to the original question
- a hearty thank you
- other (?)
If you checked any of the last four, most probably posting your contribution as an answer is not appropriate and might get deleted. Please read the answer/question faq [...and could spell out the alternatives here...]
[button: go back to answer] [button: post anyway]"
The post-anyway disabled until at least one option is selected.
The idea here is to have a combination of reminding them what should/not be posted as an answer and concrete alternative might push them into canceling.