Oats, and other foods rich in complex carbohydrates, give you gas because the undigested parts of them are a favorite snack for the bacteria that live in your colon. They metabolize the starch and produce methane gas, along with a few ketones and assorted other ingredients, that give the gas that "SBD" aroma. Got that from some ones post on a nother forum.
So, it seems like washing the groats after having cooked them may have helped by removing a lot of the starches same with washing the dry quick oats before eating them. I tried washing the oats today before eating them and the water came out milky white for quite some time, so I guess it helped.