Listing a set of rules doesn't not "logical" make.

> width looks up the tree while height looks down the tree.

> that’s why height: 100% doesn’t do what people often expect and go the full height of the screen

That's why it's "not logical", even though both sets of rules (W/H look up; W looks up H looks down) can be written down. What's the logic behind the same thing (dimensions) looking at the opposite direction? What is the mental model of the interface world where this makes sense, so that you could use that logic instead of having to rely on remembering the rule that contradicts your intuitive "logic"?