Enjoyed this Smashing Mag piece on building layouts based on line width, particularly the I’m no expert tone. Exactly what a ‘content first’ approach demands, and I think it can also be applied to sites that display forms instead of lots of paragraphs. Of course, designing for text heavy sites is a lot easier, and more fun.
Interesting to note that it makes a difference whether you aim for a certain number of characters or words per line. If it’s characters then your language doesn’t matter. If it’s words (and I’ve always aimed for 10–12 words per line because the eye shifts at a new word rather than a new character) then it’s going to affect your calculation.
(Incidentally, a width unit based on number of words per line would be interesting.)
German words are longer than English. That means German needs a wider measure than English, if you’re aiming for a certain number of words per line.
Finally, line width is complicated. Readers are pretty tough; long lines aren’t necessarily detrimental to comprehension, although they do seem to affect the reader’s experience.