Web3S supports hierarchies? Useful ones?

Update: I've added more detailed links and summaries how this could fail in my next blog post.

Web3S seems to be clearly be driven by a need for hierarchies; from the discussions (Dave, Tim, Sam), examples about books and authors, and the FAQ on why not APP:

No Hierarchy – ATOM only supports a two level hierarchy, feed and entry. It is possible, of course, to create an entry that is really a pointer to another feed but that is both painful to handle at a protocol level and inefficient when one actually wants to retrieve an entire tree as one has to make many round trips to pull in all the values as one walks the feeds.

But, later in the FAQ on hierarchies and graphs:

... we will just have to make do with hierarchical rather than graph based data formats.

So, Web3S supports hierarchies, but not graphs. Isn't the Web a graph? What does Web3S do when two articles have the same author?

My assumption was that the author element would be repeated with the same id, so I looked further and found the FAQ on ID uniqueness where we learn that the IDs are only unique within the containing element.

Am I understanding this right? Does Web3S really not have support for maintaining a single author of many articles? Do really need to track down every occurrence of one author (by data matching instead of URI) in order to correct a spelling error?

I've not done more homework on this than the FAQ, I'll keep looking. Someone please tell me I'm wrong because this would be silly.