I think some people have but I've never had much luck with the tagging system on imgflip. When i click on a tag it will only show me the memes with that tag in the stream I'm I'm at the moment not the entire site which is pointless i think i want to see where those tags occur on the whole site. If you know the tricks i would love to see. Thanks.

It can't hurt, it may even bring traffic from internet searches. The tags from my event that ran last March have a pretty good return when the tag is searched through the ImgFlip search bar. Once enough memes have been tagged with it, it will become a selectable tag. I think it'd be worth it.

Do you watch Call Me Kevin?