Poor writing, I meant that Patterns of Software was fascinating. I'd be interested to give a glance to the above though, precisely for insights like that which

Poor writing, I meant that Patterns of Software was fascinating. I'd be interested to give a glance to the above though, precisely for insights like that which you highlighted. I'm not surprised at all. Java has the same kind of situation going on, and its performance depends on the ability of the JIT compiler to kick in and perform inlining. When this is not possible (e.g. calls sites where you call a virtual method with many implementations), performance degrades a lot. This is especially bad with interfaces, which have intrinsically higher costs. As for Lisp, it can be even worse if you take things like multimethods into account.