Board Thread:Theories and Speculation/@comment-27082825-20150116155842/@comment-26023629-20150122165538

Oh, no, "holds water" is just an expression- I meant, if the theory stands up to scrutiny. Sorry, that's kind of a confusing expression to use in this situation.

Actually, I just thought of another possible reason for Mei having two advanced natures with a shared element, but no kekkei tota: the kekkei tota requires the genes for all of the two part natures that contain those three elements to work. Mei has futton and yoton, but has no genes for mokuton; so they couldn't combine into a three- part nature. As in, she can mix fire with water, and fire with earth, but she can't mix earth with water, so she can't possibly mix all three. It would make sense: we've seen all three advanced natures containing earth, wind, and fire in and near the Land of Earth, and it wouldn't be unreasonable for Mu's clan to abduct scorch and magnet users from their native lands nearby. Mokuton, meanwhile, could never be found in anyone but Hashirama, so Mei could never have a kekkei tota. And, with wind+lightning and fire+lightning still undiscovered, other kekkei tota would be nigh impossible to make, explaining why nobody elese ever succeeded in doing so.