Approximations
Avoid checking the “satisfied” status of other classes
Ancestors-Only approximation:
a class can continue unregulated if
- the class is not overlimit, OR
- the class has an underlimit ancestor
A class can be regulated unnecessarily
An overlimit class can continue unregulated until its parent is labeled not underlimit, even if a sibling class is unsatisfied
a class can continue unregulated if
- the class is not overlimit, OR
- the class has an underlimit ancestor whose level is at most Top-Level
Top-Level indicates the highest level from which a class can borrow (infinity in Ancestors-Only, 1 means parent status not checked)