State of the art of XSLT testing in a simple succinct format by Tony Graham.
Creating a working stylesheet may seem like an end in itself, but once it’s written you may want it to run faster or you may not be sure that the output is correct (And if you are sure, how sure are you?).
Profilers, unit test frameworks, and other tools of conventional programming are similarly available for XSLT but are not widely used. This presentation surveys the available tools for ensuring the quality of your XSLT.
Have you read any of Cem Kaner's books? He is such a great author, I have read all of his books and learned so much from them. I was fortunate enough to see him give a presentation a few years ago on his methodology. He is as good a speaker as he is an author. Do you know of any other authors of Kaner's reputation?