Expert

someone widely recognized as a reliable source of technique or skill whose faculty for judging or deciding rightly, justly, or wisely is accorded authority and status by their peers or the public in a specific well-distinguished domain (Context). http://en.wikipedia.org/wiki/Expert

cf: Talent, meritocracy

having tacit knowledge, too?

not quite mastery? or the same?

10x? (You Are Not)