That depends heavily on the language used. In Lisp you can have code blocks that are clearly independent units hanging 50 characters off to the right. A limit

That depends heavily on the language used. In Lisp you can have code blocks that are clearly independent units hanging 50 characters off to the right. A limit of 80 would limit the lines in the code block to 30 characters, which is not enough. Lisp tends to have pretty long function names, like multiple-value-bind or with-open-file.