I just got a flag declined for flagging this answer as "not an answer". The flagging comment stated "declined - Almost by definition, an accepted answer is an answer. Pointless or bad answer should be downvoted." I was a bit surprised since I made the flag in good faith (see the September 2011 Newsletter about flagging). Yeah, I was also a little bit annoyed at losing 10 flag weight, but I'll get over it by the time I post this.
What I really want to know is if the declined flag comment is correct. Should I bypass accepted answers that are clearly comments and not answers? I admit that this is probably a rare situation, but I want to be a better flagger and would like to know what is best practice.
As a more general question, is there a flagging faq that covers all the intricacies of flagging, or at least the best practices? I've been searching for "flag" on meta for days and reading all I can to educate myself. However, I have 18 flags with 3 declined which leaves me with the feeling that I'm missing some fundamental understanding of what's acceptable to flag and what's not. I want to do better than that.