Lower-case words have a wider variety of shape, as so many letters have markings extending above and below the horizontal lines that bound the letter o. UPPER-CASE WORDS ARE BASICALLY ALL RECTANGLES OF VARYING WIDTH AND FIXED HEIGHT. BUT THEY USE MUCH LESS WHITESPACE, WHICH IS WHAT LOWER-CASE WORDS USE TO CARVE OUT SHAPE.
I believe the result is that lower-case words are easier to read at sufficiently close distance but legibility drops off sooner as distance increases. I also believe that while upper-case words may be less legible, individual letters are more legible as upper-case, and therefore upper-case words may be easier for very inexperienced readers who haven’t learned words by shape and still piece them together by letter.
Word shape is not a well-supported theory of reading. Very skilled and practiced readers are still going letter by letter.
"The result" is that if you pull people off the street and ask them to read capitalized or lower-case text, they're slower at reading the capitalized text. People like pasabagi want to leap to the conclusion that that means reading capitalized text is harder. That conclusion is unjustified; the rest of the result is that the difference in reading speed disappears after a small amount of practice. Lowercase text is more common. But obviously that can't justify the choice of a writing system; any writing system will be common if it's in common use.
I second the neighbor's request for references, since your claim goes against the accepted ‘wisdom.’
Note also that your claims don't actually refute pasabagi's original conclusion. If lowercase text is easier to read because of its ubiquity, this still means we should use lowercase text—the same way that we use the right-hand rule for screwing things in and out. Books, and lowercase, were around longer than telegraph.
> since your claim goes against the accepted ‘wisdom.’
This is overly generous as a description of a collection of myths that have been known false for decades.
> Note also that your claims don't actually refute pasabagi's original conclusion. If lowercase text is easier to read because of its ubiquity, this still means we should use lowercase text
No, it doesn't, because if we ignore your advice and use capitalized text, capitalized text will be common enough that the advantage of lowercase text disappears.
> if we ignore your advice and use capitalized text, capitalized text will be common enough that the advantage of lowercase text disappears
I see you're talking about some alternative universe where you convince significant portion of publishers (if not a majority) to switch to uppercase. The practical question is, did teletype or early programming languages or road signs flip us over to that universe? Doesn't seem so. In the world where I am, lowercase text is more legible because it's ubiquitous.
If we ignore your advice and use capitalized text only for programming in, while books are still published in mostly lowercase, capitals will be so common for programmers that lowercase text will have no advantage over capitalized text.
The styles don't compete with each other for space in your mind. It's just a question of whether you're used to them.
Your ideas seem a bit counter-intuitive, so I'll assume they're coming from some literature, and I guess I can't really comment on literature I haven't read. All the stuff I've found (partially what motivated my interest in the first place) were studies showing the opposite, written in the days when ALLCAPS was the normal form of written communication.
I believe the result is that lower-case words are easier to read at sufficiently close distance but legibility drops off sooner as distance increases. I also believe that while upper-case words may be less legible, individual letters are more legible as upper-case, and therefore upper-case words may be easier for very inexperienced readers who haven’t learned words by shape and still piece them together by letter.