DTD's....

Ok, we all know about the provided DTD... and I've tried the improved DTD that's posted with little to no success at all.So, I created my own. I created it and I'm studying it in depth to learn the relationships between, and requirements of, the tags themselves.But we all know, of course, that this does nothing to help learn RPN or the exact syntaxes of stack operations and logic statements. That's ok, we have a lot of great resources for those things already... enough to fry my two little brain cells, at least!My question is two-fold:A) Has anyone else created working DTD's and tried to write anything up that explains the realtionships between the tags? I'm doing this for my own benefit, and wondering if I should arrange my notes in the form of a guide that would allow others to read it.:( Would there be any interest in such a thing?I'm already well on the way and have put about 20 hours of work into it so far. I have to admit, I'm learning more from hand picking my way through the DTD than I ever thought I would have!Just testing the waters to see if it's already been done and, if not, to see what the level of interest may, or may not, be.Scott / Vorlin