After much research, I think I can wrap my brain around WP's rewrite system. I would like to know, though, how to properly test rewrite rules to see if the right rule/tags is being used and the right query vars are being passed. Is there a way to create a temporary template that supersedes everything in a theme whose sole purpose is to spit out current query_vars?
Check out my favorite Rewrite Analyzer plugin written by @Jan Fabry. It allows you to analyze your rewrite rules and really helps in debugging those rules.