Yeah, this is why the "You won’t need many" line is where I stopped reading. Developers who say "most of your LIs are gonna be indented" and "most of your elements will need a top/bottom margin" or "your font sizes will all be relative to the font size of the container" aren't building even slightly complicated UIs...but that doesn't stop them from passing around these "just write CSS, dummy" posts once every few months.
If you write CSS for your personal blog and want to mass-apply styles to save time, go for it, but I think the majority of people who write CSS as a part of their daily work will find that this attitude creates more headaches than time savings.
If you write CSS for your personal blog and want to mass-apply styles to save time, go for it, but I think the majority of people who write CSS as a part of their daily work will find that this attitude creates more headaches than time savings.