Actually, the biggest clue is that Kunou never refers to her as
"the red-headed girl" which would be onna-Ranma's most obvious feature.
Instead he calls her "osage no onna", roughly "pigtailed girl."

This is not a clue at all!  As far as I know most anime worlds contain people
with hair from every colour in the rainbow.  It would be normal in the

<snip>

imaginalbe so what kind of "clue" is that?!

Okay, so there are some people with odd-colored hair. But remember, this is
in a culture where most people have BLACK hair, and even in anime, these
oddball hair colors are far less common than natural shades. And in the
manga, most of the people DO have black hair. There might be many people
with odd-colored hair in Nerima, but that is still a small percentage of
the total.

Besides, red hair is more distiguishing a feature than a pigtail. Any fool
with long hair can have a pigtail. But fire-engine red hair, that's
SPECIAL. And Kunou, and everyone else, doesn't appear to notice it.

BTW, a lot of people tell me R.T.'s colour works of Ranma more often
than not has Ranma-chan's hair coloured a bright fire-engine RED so
there!

So what? RT, and indeed most artist, don't color their own work. Coloring
is tedeous and she has better things to do, like draw more Ranma :). She
probably didn't even know that the color was being used for Ranma-chan's
hair. The colorer maybe did it in response to th anime. Or maybe he/she
just plain goofed and thought Ranma-chan was SUPPOSED to have red hair.
This kind of miscommunication occurs all the time in comic industry here,
and I imagine the same things happen there.

Furthermore, the early jackets for the volumes have Ranma-chan with black hair.

                           ---------------------
-wyrm(AKA Tom Jefferys; Time Lord for Hire, "Have TARDIS; Will Travel.")
<wyrm@mail.utexas.edu>                       <JEFFERYSTR@rascal.guilford.edu>
Member of the AFSS          Depraived Kawaii Thing of the First Order, Martin
   =<SIG>= Wyrm-chan @_@ H-Wyrm @_@ Ten @_@ Chibi-Usa @_@ Azusa =</SIG>=
=<^_^>= R1/2#_#BGC#_#Sailor Moon#_#Dr Who#_#Star Trek#_#Monty Python =</^_^>=

"DINSDALE!!!" -Spiny Norman