Originally Posted by acidrain
This makes absolutely no sense... you were already over carbed, so you bubbled co'2 through the dip tube, and now it's better? Am I missing something?
The agitation from the large bubbles of gas coming up knocks a lot of co2 out of solution. This only works when there's no pressure in the headspace, so that there's somewhere for the excess gas to go. It can quickly reduce the carbonation to just a little more than the beer will hold at your serving temp and atmospheric pressure.