Yikes! That's also a great cautionary tale for Primitive Obsession/Whole Value as well as a bunch of other design principles.

I'm thinking about how I'd have done that refactoring and now I wish I had the code base to try it on. It sounds like it would make a really good real-life exercise in a workshop. "Remember folks, you have to get this right. There's not really a way to check this with the real hardware, and if you get it wrong, someone's going to get hurt."

Thanks again.