WD-webarch-20031209: Delegation of authority in hierarchical URIs

Section 2.2, bulleted list, first item.  It would be useful, I think,
if this were expounded at greater length.  It is not necessarily clear
to all readers (it is, for example, not entirely clear to me) how the
hierarchical delegation here postulated follows from the wording of
the specifications defining the HTTP and mailto schemes.