The phrase "a superior command" is correct and usable in written English.
It can be used to describe a higher level of authority or control over a situation or group.
Example: "The general's strategic planning demonstrated a superior command of military tactics."
Alternatives: "an elevated authority" or "a dominant control".
The more conservative Wall Street Journal is fulsome in its praise for Mitt: he appeared Presidential, "showed a superior command of fact and argument than the incumbent, and made a confident, optimistic case for change".
In fact, when he was assigned to Kentucky, he informed Abraham Lincoln of his "extreme desire to serve in a subordinate capacity, and in no event to be left in a superior command".
Bush pointed with particular pride to the fact that seventy-four per cent of those polled said that, of the two Bush brothers, he had a "far superior command of the English language".
It, too, is a collaboration with her son, which Ms. Ono relished both because she thinks he is an extraordinary talent ("I'm very lucky as a mother because I didn't know when I impregnated him and he came out in the world that I was getting a good musician for my albums") and because she saw him as having a vastly superior command of "modern technology".
In an industry that's changing, superior command of language is even more important for CEOs.
Two regimes, each eager to assert what Crowley and Pavitt call "its superior command of modernity," engaged in a long-running rivalry played out in weapons, skyscrapers, satellites and refrigerators.
Like an admiral commanding a flotilla that his underfunded opponent cannot hope to match, Nabokov lords his superior command of Russian language and prosody over his opponent.
Karsay threw hard and had superior command and mechanics.
Because of his superior command, Rivera spots his cutter in and out, up and down.
The wild rookie whom Righetti knew with the Yankees in the late 80's now has superior command of his cutter.
Meanwhile, his pitching style – which relies on superior command and out-smarting batters – has aged well.
