[cmjqol]

That was one the clearest guideline description I've ever readen in my life.

Obviously I'm not surprise this was written by an Engineer , it's very clear about what to do and what not.

Usually trainings and guidelines made from Designer are useless to developer , they talk about emotion , colors , moods etc... Which is key for marketing and UX but does not help a developer improve it's skill in UI .

[deltron3030]

Skill in UI, or if something should work generally for everybody, or optimized for a specific audience, is audience dependent. Design is basically cultural anthropology, extracting real world types and positioning products to adress those types.

Technically it's tough to sperate both worlds, because layout (grids) and behavior (transitions, animations) have strong stylistic implications. This then means that a developer skilled in UI (making it work generally) can't adress specific audiences, most likely racing to the bottom (too many others doing the same and competing for the same general audience).