>just wish there was a better way to debug xpaths that can't be matched
First: don't try to use the browser as a development environment. It's the worst possible environment for debugging. Use Stylus Studio or XML Spy, or just a text editor and command line XSLT processor such as Saxon.
Second: The advanced solution is to use schema-aware transformations with XSLT 2.0. See http://www.stylusstudio.com/schema_aware.html
- the idea here is that if the XSLT processor knows about the schema for your source document, then it can detect invalid paths at compile time.
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference