I like your terminology of code locality. Personally, I've always thought of it as being the "ctrl+f" principle. If I'm reviewing a PR or looking at the source

I like your terminology of code locality. Personally, I've always thought of it as being the "ctrl+f" principle. If I'm reviewing a PR or looking at the source in GitHub, it's a lot easier if I can find definitions via "ctrl+f" without resorting to an IDE. Sure, it's probably best practice to checkout code changes I'm reviewing and open them in an IDE, but that often isn't what happens in practice and if I'm reading third party code, configuring the IDE to understand the project might take a lot of effort. The stronger rule is that it should not be necessary to use a stronger tool than a project wide find to lookup references to some function/data structure.