My thoughts the same. Frontend dev is too forgiving as an interactive playground that I tend to iterate on the solution by getting some feedback from feeling things out rather than straight up knowledge.
I would replace "too forgiving" with "provides such an excellent feedback loop". It's the reason languages like Lisp have a REPL. :)
I would say HTML is too unintuitive.
I would say that the Box model is unintuitive.
I agree, these question assume some kind of drill approach with the language syntax. I would think, this drill only is learned at a university/college level, and if you start programming from a different angle, these questions are hard to answer.
These are things that I understand when pointed out to me, but off the top of my head, with no google, I'd have to think for a second. They are things that I implement most every day. For instance, the position fixed/absolute thing... I work with things like that pretty much every day, but usually it takes me 10 minutes of fiddling, or 50 seconds of googling if I've had to do it before, unless I get lucky and it just reveals itself as obvious.
Oh well, I suppose that's why I live in the sticks and freelance instead of working for Twitter or Stripe :D I mean, this stuff seems esoteric to me, even though I work with it every day... it's neat to know that there are a lot of folks who have this stuff wired well enough to do it with no reference material.