I was wondering should the Tumbleweed badge include self-answered questions with no other comments or answers?
I managed this myself last week.
If you really want to get the Tumbleweed badge for a question like that, a better idea would be to wait until you get the badge, then answer it yourself.
If your own answers didn't apply, you could answer your own question immediately, thereby discouraging other people from looking at it (since it already has an answer), and very easily earn the badge. This works best in the remote tags which get low enough activity without answers, having an answer really makes it skip-worthy.
Alternatively, just delete your answer while it still has insufficient viewing. This kinda invalidates the idea of preventing the scheme I just described since it is able to be accomplished. Nevertheless, I don't think we should cut the middle man here and just allow it with a self-answer.