He didn't need to abuse any existing program by adding new
flags or the like; unless I am mistaken, `sed Nq', for some
number `N', does exactly what `head -N' would do on a single
file, obviating the very need for head(1).
To summarize this discussion:
cat -v should be a separate executable and not a command line option. That's the Unix way.
head isn't needed because we can already do it with the command line options for sed. That's the Unix way.