From the Discovery Channel
Do Valentines Hinder Love?
Senders of greeting cards and valentines may actually use the cards to distance themselves from their feelings, reflecting a culture in which relationships, due to social and economic pressures, are “necessarily temporary,” according to a new book by an Ohio State University professor [Barry Shank].
…He also mentioned that collections of cards from individuals revealed that senders often would write exactly the same thing to different lovers.
..favored at the time were “vinegar” valentines that Shank said “policed class boundaries.”
Examples include a card that addressed the recipient as, “You nasty old bachelor.” Yet another had the line, “You want to be my steady male? Well, go stick your head in a pail.“