The dissolved oxygen is going into the GI track, not the lungs. The stomach and intestines do not absorb oxygen - the membranes are not designed for the same gas exchange that takes place in the lungs. Therefore, it may be that the oxygen is inactivating some of the alcohol before it is absorbed. Perhaps through oxidation, although O2 is not a good oxidizer. Maybe there is some ozone (O3)? If this happens in the GI track, why can't it happen in the bottle? Were the blood alcohol levels immediately after drinking the same, or were they lower from the start after the hyper-oxygenated booze? If some oxygen is absorbed from the stoamch, can you get the same effect by sucking on oxygen from a tank or even a hyperbaric chamber?