Can you give an example where JavaScript would “enhance the presentation of the document”?

You mean like scroll-jacking? Some script that prevents me from copying and pasting? Something that loads images later for some reason and shifts everything around?

I don’t mean to be facetious, I am genuinely curious what you mean. In my experience JS has been nothing but a detriment (for reading documents, that is), and I have it disabled on all of my computers.