Just to clarify: tags, or anything else, that appear to be trolling or flaming shouldn't be used even where the intention is not to do so, and even where the "victim" knows this. The reason is twofold. First, people who do intend to upset the victim might claim that it's just a joke or that the victim knows it's meant in good fun, and we don't want that to be a legitimate excuse. Second, people who don't know the context or individuals involved might see it and think we allow victimisation of the kind that it appears to be. So those tags shouldn't have been used even if the intention was benign and understood to be so.