> Frank's example is an attack on the second possible way to
> trigger the O(n^2) behavior. See msg150724 further above where I
> listed the two possibilities:
> 
> """
> An attack can be based on trying to find many objects with the same
> hash value, or trying to find many objects that, as they get inserted
> into a dictionary, very often cause collisions due to the collision
> resolution algorithm not finding a free slot.
> """

No, Frank's examples attack both possible ways.