On potential originality of content, I'd vote yes.

But then for me a book titled WWDtStK would be a bit like my Middlemost but with an undertone of a little more, and possibly a bit darker, emphasis on the What. So, at least a little bit of wit/irony on a seemingly standard fantasy plot but with a darker thinky edge of exactly what saving a 'kingdom' entails (and that could be a non-fantasy kingdom so long as there was a fantasy feel to the plot). Middlemost, but with more about 'doing what needs must be done' and what that costs the people who do it. Not humour, but characters with a sense of humour.

And I think I'd find it memorable -- I'm prone to remembering stories but forgetting titles. Clearly someone thought *those* titles were memorable, so my taste in quirky meaningful is not relevent to market fetishes. Which I guess means, I like it and an editor who loves the book may like it -- but possibly not (given one agent sent me a form rejection referring to Artemis rather than The Middlemost Child, I may also have a titling problem) :)