OCL25 — How indeterminate are asOrderedSet/asSequence?

asOrderedSet() : OrderedSet(T)
Redefines the Collection operation. An OrderedSet that contains all the elements from self, in undefined order.

If asOrderedSet() is invoked more than once on the same Set, then presumably the subsequent calls have a defined order; the order previously used.

When used by QVTo the lack of determinism of Set ordering is a significant debugging nuisance. Suggest that there is a repeatable but unspecified underlying order determined perhaps by object creation order.