<Cherub_Enjel> Wise words. I also know some 2100-2200 players who are almost like that... playing anything under the moon and sun to start the game, maybe getting some inferiority - but then fighting with superior positional and tactical understanding - and above everything else, with a lot of patience, some precision and a lot of will to fight!
Some people enjoy studying the openings - which is all good.
There's no harm in playing the theoretical variation right up to move eighteen or twenty-six with a like-minded (low-rated) fellow - or even catching someone with your favorite opening trap, and gaining some points...
Of course, the great majority of games isn't decided that way - and once opponents learn that a (lower-rated) player leans heavily on theory - they will play something else, maybe non-theoretical, to test that player's chess.
After a couple of years of study and play, the theory-lover is generally pretty much awakened from the illusion that this is what will make a chess player out of him. He may still love opening theory - which isn't a bad thing in itself.
And I'd suggest playing a real opening of course, without studying it forever, because why not, but I'm just showing how strong tactics and decent positional understanding (out of the opening) pretty much overrides openings at the level right under titled.
In his game against me, he actually missed a tactic in a complicated position that gave him perpetual check, so it's not like he was tactically flawless either, just strong.