He managed to get a statement to go as fast the JVM could possibly go, and he did this by getting the code to write code (the code added type castings to every variable, which apparently gave the JVM the info it needed to optimize like crazy). And there is no way to do that without hard-coding, and if you don't know what kind of data you are going to get, then obviously there is no way to hard-code anything. In other words, this kind of stunt can only be done in a language that allows this kind of code-that-writes-code.
http://www.learningclojure.com/2010/09/clojure-faster-than-m...
He managed to get a statement to go as fast the JVM could possibly go, and he did this by getting the code to write code (the code added type castings to every variable, which apparently gave the JVM the info it needed to optimize like crazy). And there is no way to do that without hard-coding, and if you don't know what kind of data you are going to get, then obviously there is no way to hard-code anything. In other words, this kind of stunt can only be done in a language that allows this kind of code-that-writes-code.