Well more supply tends to cause downward ASP pressure compared to less supply - ALL OTHER THINGS BEING EQUAL.
But we are talking about 2013, 2014. Who knows what demand will be like then.
Samsung is building in the expectation that system memory and solid-state disk drives will be a big driver by then AND because it probaly want to turn some of its fabs over to its foundry division: a process already started.
If demand does not materialize or there is some sort of economic catastrophe it may have to ramp some of these facilities slowly.. But once it has the approval and the shell it is in a position to control that.