Many of us, sometimes for good reasons, have a habit of thinking performance is the most important thing. However, in this case, focusing on that one sentence o

Many of us, sometimes for good reasons, have a habit of thinking performance is the most important thing. However, in this case, focusing on that one sentence overlooks the spirit in which the talk was given: to educate. There is some key context that you might not get from the InfoQ article. Glenn's talk, as presented at ClojureConj, emphasized the educational benefits of comparing the original procedural style with an adapted functional style. Another message that came across is that we've lost a historical appreciation of our tools. It is very easy to frown upon the techniques that TeX used. In context, many of them were reasonable (if not state-of-the-art) given the constraints of the time. It seems to me that it would be quite challenging to dig in and unpack the original intention of TeX and translate it to a modern functional language. I tend to believe that a Clojure version could be made almost as fast, if not faster, given more effort, without destroying understandability.