Dear Richard:
The rule change you refer to is with regard to changing non-immigrant visa status from visitor to student while in the US. The old rule allowed you start studying immediately after filing the application. The new rule requires you to wait for the application to change status to be approved before you start studying. This rule change is included in the voluminous copy of the immigration regulations you posted previously.
Changing visa status from visitor to student is a completely different animal to recreational flying on an visa waiver.
Best wishes,
Campbell