Neat! As others have pointed out, much depends not
on the abstraction of the modeling technique, but on
the method to be applied to the markup (ie, the application).
If I want a tracking system for the person,
the pointer techniques are good. If
I want to render a title or find all titles, then the
explicit element declaration is good.
BTW: All of this is why DTDs have worked well
for so many years. They are a contract between
implementors and systems.
The funniest thing I've seen lately is a statement
on the Microsoft XML site that XML gets rid of
committees who design DTDs in favor of a
more "organic" approach. Lots of luck. ;-)
len