It depends if its funny, but I have something that would serve that purpose!
Well I would take it lightly as long as it is intended as a joke or something (that the author is naively forwarding something which she recieved in email and not trying to come up with some "ideas" of own). Well if she really doesn't know the answer (or myth, or tradition whatever), then I would say its pity to make jokes.
The red dot as known as "bindi" is usually considered a symbol of marital status for hindu woman ( so scratching it off is something not so sacred I would say). Usually after marriage the women wear the bindi, ( well in cities atleast during some religious functions!)
And if in case you guys want some kind of jokes well here are few that I found!!!
Some annoying "Indian" questions and the answers (the last one is my favorite, no offense but thats when it starts getting on your nerves!):
Q. What does that red dot on women's forehead mean?
A. Well, in ancient times, Indian men used to practice archery
skills by target practicing by aiming at their wife's red dot. In
fact, that is one of the reasons why they had many wives. You see,
once they mastered the art of archery and hit the target....
Q. You're from India, aren't you? I have read so much about the
country. All the wonderful places, the forests, the snake charmers,
the elephants. Do you still use elephants for transportation?
[note: This one we were actually asked in August '93 by a real
estate agent when house-hunting in Boston.]
A. Absolutely. In fact we used to have our own elephant in
our house. But later, we started elephant-pooling with our neighbors,
to save the air. You see elephants have an "emissions" problem.....
Q. How come you speak English so well?
A. You see when the British were ruling India, they employed Indians
as servants. It took too long for the Indians to learn English. So the
British isolated an "English-language" gene and infused their
servants' babies with it and since then all babies born are born
speaking English.
A variation to the above is a compliment ---
"You speak very good English."
Response: Thanks. So do you.
Q. Are you a Hindi?
A. Yes. I am spoken everyday in Northern India.
Q. Do you speak Hindu?
A. Yes, I also speak Jewish, Islam and Christianity.
Q. Why do you sometimes wear Indian clothes to work?
A. I prefer it to coming naked.
Q. How do you celebrate Thanksgiving day in India?
A. By roasting an American....