That's why I focussed on Mongolia, and should have emphasized that china should not be thought of as part of mongolia after the fall of the Yuan. It was indeed most of the driving force for the temporary increase in Mongolian sophistication. Maybe we don't want to think of the "china phase" as geographic china but Chinese knowhow?

Another way in which geographic china doesn't fit into the scheme but historical Mongolia does is that china has never really been a closed system. Geographic Mongolia however was landlocked like the closed system in the featured article. (And this is why they fought hard but failed to expand to the seas)