Any custom of etiquette can be called a punctilio, especially if it seems a bit silly. Your grandfather's punctilio of announcing his name when he answers the phone might seem silly to you.
Men holding doors open for women seems pretty old fashioned to many young people — and a little bit sexist, too. Some older men, however, will stick to this punctilio because they feel it would be rude not to do it. Punctilio comes from the Spanish puntillo, or "little point."