This statement suggests to me that you missed the entire point of Gruber's essay. You are right that I made my point overly trivial. It was supposed to be the

This statement suggests to me that you missed the entire point of Gruber's essay. You are right that I made my point overly trivial. It was supposed to be the extreme case of understanding the importance of UI design: how it looks and works is very important. I've designed many interfaces, but I am not a designer. Understanding the user, how they use the system, and how the system needs to react to that use is what matters. You can build a great UI without being pixel-perfect, but, in my experience, engineering teams who fight pixel-perfect will fight the effort that it takes to understand what a great UI for their system is.