"As a programmer with more than 20 years experience with over a dozen languages, XSLT templates and default rules were not obvious to me. Over the past year or two I had looked at numerous examples trying to discern how they worked. While I could understand the general gist of what was occurring, there was too much implied behavior that I did not pick up. It was not until going through formal XSLT training that I fully understood how XSLT worked. Clearly, if the barrier to entry is that high for an experienced programmer, the average web developer was not going to find this technology very useful."Link