Importantly, tags are NOT comments. They are supposed to be descriptive of the image. If you look at a picture and you go “Wait, what!?” then you should make a comment to that effect, NOT add “wait what” as a new tag for the image. Otherwise you just clutter up the tagging system with pointless dross. In fact, an overabundance of metatags like this is part of the problem that made ponibooru so slow in the first place! Derpibooru’s code is more efficient, but you should still try and avoid making pointless tags.