However, on my screen, called 14", about 12.5" wide, the text is about 100 characters per line in about 7.5" for about 13.33 characters per inch horizontally.
Then with two pair of strong reading glasses and my nose 5" from the screen, I can barely read the text.
A shame because about half the width of the screen is given over to just a table of contents with mostly blank space.
Maybe if I had a video screen 4 feet wide?
More generally, yes, I know, there is a lot of careful, sophisticated, deep work in user interface, but for the OP pages I'd like to see only about 60 characters per line and about 6 characters per inch horizontally. About 8 characters per inch is my upper limit.
Sure if my screen were twice as wide, then I could get the present 13 characters per inch down to 7.5, but these days with laptops and tables, screens 25" inches wide are not near the 'median'.
13 characters per inch I just can't read without a lot of effort.
Generally, in Web screens, we are free to use about all the length we want but should be very careful about using up screen width.
In my start-up, each screen is just 800 pixels wide with high contrast and large fonts, about 25 pixels high on lines 35 pixels high.
Here I'd like to encourage Web page designers to use larger fonts, narrower pages, and fewer characters per line.