I think that you are overthinking it, this sort of troubleshooting doesn't require all that much domain specific knowledge (certainly the author of the article

I think that you are overthinking it, this sort of troubleshooting doesn't require all that much domain specific knowledge (certainly the author of the article came at it with more than was strictly necessary). If you install new fancy fuel injection nozzles in your car, and suddenly your car is shit, then swap them back out and see if the problem goes away. After you determine that it does, you can start investigating if the installation was botched or if they are broken, or whatever. You don't need to know anything about cars to do that, it's just generic troubleshooting.