> * Are there any obvious pitfalls or problems with this
> approach? (Or any not so obvious?) How does it compare to
> other methods?

I'm inclined to think that a general purpose pipeline processor will do the
job better. It's likely to have memory management that's better adapted to
this kind of work, and debugging facilities to examine the documents at any
stage of the pipeline or to switch validation of intermediate steps on and
off, etc. If you're lucky it might even allow distributed or asynchronous
execution of the pipeline.

Does XProc fit here?

http://www.w3.org/TR/xproc/ (or http://xproc.org)

As an aside,  if your architecture is batch transforming directories,
where multiple transforms are performed in sequence, then Kernow [1]
might be a good fit.

Cheers,
Wendell

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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
17 West Jefferson Street                    Direct Phone: 301/315-9635
Suite 207                                          Phone: 301/315-9631
Rockville, MD  20850                                 Fax: 301/315-8285
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