Decades of research show that long line lengths cause people to read more slowly, although it is of course possible that you process text differently than most.
"Ridiculously" short is another matter, but by my count, "significantly wider than your hand at arm's length" means well above 20 words per line.
"Ridiculously" short is another matter, but by my count, "significantly wider than your hand at arm's length" means well above 20 words per line.