XSLT look like a logical way of representing the data structure. However, it also looks like I would have to spend some time learning about this system. I may come back to it in the future. Is there first class perl module support for XSLT?
Comment on Re: Re: Removing duplicate subtrees from XML
XSLT is a language based on very different principles than Perl. It is very popular for XML transformation (although I could never quite figure out why ;--). See Recommend XSL module for a list of Perl modules that support it (usually by interfacing with external XSLT engines).