I love both that his Killing Magic, and apparently magic in general, is/was effectively like technology, and his had been studied by others and eventually became something akin to being "outdated", in that everyone had "caught up" to it and how it worked and what it was.
...but also that he was able to more or less instantly hone in on the flaws of the newer defensive techniques solely from a basic description of it. He may have died like a complete mook, but I can believe that he was actually a pretty decent spellcaster back in his day.