Apples and Oranges. HTML works well as a subset of SGML because it is
*mostly* doing exactly what SGML was intended for -- marking up text.
Our application is almost entirely different. I'm very nearly certain
that attempting to use SGML as our basis would be a disaster, because
it's just not intended for this sort of purpose. (Does SGML have *any*
relevant commands? I'd be surprised...)
Using standards is a Good Thing, but you have to pick the right standard...
Random Quote du Jour:
"Some people simply should *not* be allowed to play around nerve gas."
-- Professor Moriarty