For any member of a collection, it is possible to discover whether it is an internal or a referential member. The ordering mechanism is sufficiently standardized that different applications and servers can operate on the same ordering without private agreement. Basically, some folks were leery of the word 'mechanism'. The semantics of an ordering are discoverable. Agreed, but only after much discussion.
Some folks asks for a definition of 'ordering semantics'.
When a client requests a listing of the members of a collection, it can specify the ordering to be applied, and the server will apply that ordering to its response. It is possible to order the members of a collection in an arbitrary way, not necessarily based on property values. Agreed with the word 'arbitrary' changed to 'client-specified'. One way we got into trouble here is that since the ordering might well be stored in a property, it's hard to think of an ordering that is NOT based on a property value. Also, there was much sentiment that DASL should support sorting on property values, and that orderings based on property values alone should be left to DASL and not addressed here.