Let's make sure we know the difference between oxidation and oxygenation. Oxidation is responsible for the alcohol in your beer! Starches (from whatever grain with which you're brewing) are (long story short) oxidized into carbon dioxide (bubbles) and ethanol (drunk). Oxygenation is the infusion of gaseous oxygen into a medium. Granted, an excess of dissolved diatomic oxygen in your beer may speed up oxidation a little bit, it's nowhere near the rate of enzymatic oxidation that occurs during the fermenting process. Especially if the beer is kept cold enough (as it should be anyway) during and after oxygenation, free oxygen isn't going to mess up your brew.