> During most of the TMI accident the core was being actively cooled.
Steam is not a coolant, which is why I went into so much detail on my first point. In fact steam has such atrocious heat conduction properties compared to water that you'll find many nuclear engineers refer to "steam blankets".
So if the coolant pumps were running or not is essentially immaterial if the coolant flowing over the fuel plates is itself steam. I only said the coolant pumps were the last line of defense. They are required, but not sufficient.
This doesn't make the original article any more correct though. During most of the TMI accident the core was being actively cooled, and in fact it never got uncovered enough to even completely melt. So this still does not tell us anything about how containment would work in the absence of cooling.