This is a Most Righteous Answer, kissing cousin to The Correct Answer.

Repeating myself, sorry:

I've done a lot of electronic medical records. At the time, SOAP, WSDL, HL7 3.x (XML format) reigned.

Techniques like yours is how our two person team was able to run circles around our much larger partners. In other words, while they were stuck trying to update and compile the XSDs, we just treated inbound data as screen scrapping.

Sharing a tip of my own: while xpath expressions are mostly great, we migrated to globbing expressions. The wildcarding allowed our scrappers to be a lot more flexible, robust in regards to all the chaotic mutant data we were receiving.

https://en.wikipedia.org/wiki/Glob_%28programming%29

PS- IMHO, The Correct Answer is to have path expression intrinsics, built right into the language. What LINQ should have been. Imagine if Java had regex intrinsics like Perl, instead of that weird library. Some idea.