> I thought that you might have specific experience with "real world" applications, thus my question.

As to this point: I don't at present have "real world" experience writing CLIPS. My experience thus far has been entirely research-driven based on observations I've made in "real world" scenarios.

If you want to read about some other people who have used CLIPS in real world scenarios, here's the most comprehensive HN thread to date so far on the subject:

https://news.ycombinator.com/item?id=40201729 - 30 days ago

One in particular that stands out to me is the usage of CLIPS in MTG:Arena, a real-time web-based card game with and arguably large amount of rules.