Dear Mary: How will Joan Collins introduce herself now she’s a dame?

Q. We enjoyed the Christmas University Challenge series featuring mature graduates, some of whom were more in the public eye than others. I was a little surprised that one team captain, a broadcaster at that, introduced herself as Dame X. I was always told that I must not introduce myself as Mr and that it was a title bestowed by others and not by oneself. I expect the same to apply should I ever become a Sir. As that is extremely unlikely, I ask merely out of interest and for the benefit of our beloved and newly be-knighted Dame Joan of these pages. I am sure she knows the protocol already but I should hate to think less of her if my logic is incorrect.
— R.B., London SW3

A. Of course Dame Joan knows the protocol. Moreover, she needs no introduction but, should one be needed in some formal setting, no doubt she is always accompanied by an attendant who will spell out the details to spare her the immodesty of giving them.