That isn't true, at least.. it should be.
the extra oil is in the sump. and stays there until there is a drop in oil pressure(too much going to the heads, not enough coming back down, etc) THEN the sump drops the extra oil for as long as it needs to/can to bring the pressure back to the specified level.
Once it achieves that level, the sump closes, regains its 2qt capacity, and life goes on inside your engine with the stock amount of oil.
