So then I have a question

With my "off with their heads" thread, was it in-appropropiate to use the violence warning?

My belief is that I would rather know ahead of time that a particular post MAY contain violence, nudity etc. After all isn't lopping someone's head off a tad violent (not meaning to sound sarcastic). By the same token, should I have used a flag for my "furries" post?

Granted, I'm sure there are those that OVER-use/UNDER-use flags, but I think there will always be "grey" areas, like mine. I would like to know (and maybe it's in a post somewhere) beyond the obvious postings, when should a flag be used?

Thoughts?