Never thought I'd run into another person from Waynesboro on Hacker News of all places. But, I guess I'm here so there's at least two of us. Small world after all.
In actual production use, I think it could be better to write a separate program that will generate the code for you instead of using the C preprocessor (or use a language with this kind of introspection built in). However, using this hack lets you depend only on the facilities of the language, and that can be useful in simplifying the build process. Plus it was fun to create, too!
Very interesting article, refreshing as well to see a criticism of systemd based on technical details. Unlike most other criticisms of systemd, this author does not resort to personal attacks and insults against Lennart Poettering or fear-mongering appeals to tradition. I still think systemd is an improvement over the previous sysvinit, but the author seems to have found some real conceptual flaws with systemd that are somewhat unsettling.
I hope this article can start some actually useful conversations about init systems that do not fall into the pitfalls of FUD and negativity that seem to have surrounded this topic in the past.