One doesn't need to know everything to be a master. I bet even when you do learn new things that you adapt your knowledge to them just fine.

But since when is metal an element? Doesn't that fall under earth? Also thought most usages for metal would be a part of alchemy here from what the shit I read says.

[Well, at least that is something potentially of interest, except he hates Earth. But really he's just hit a plateau and doesn't see a way to get better at this point beyond new magic.]