DTD vs. XML Schema
AShocka writes "The W3C XML Schema Working Group has released the first public Working Draft of Requirements for XML
Schema 1.1. Schemas are technology for specifying and constraining
the structure of XML documents. The draft adds functionality and
clarifies the XML Schema Recommendation Part 1 and Part 2. The XML Schema Valid FAQ
highlights development issues and resources using XML Schema. This article at webmasterbase.com addresses the
XML DTDs Vs XML Schema issue.
Also see the W3C Conversion Tool from DTD to XML Schema
and other XML Schema/DTD Editors."
XML isn't that new modern language that solves all our problems. see http://www.pault.com/pault/pxml/xmlalternatives.ht ml for alternatives to xml - languages similiar to xml which solve your problem in a better way.
Most software written to use XML nowadays is only done so that programmers can tell their boss "Yes we are using XML, therefore we are trendy and should not be layed off"
There is only so much that you can optimize.
There are better and more optimized ways of representing your data.