I have just given my surname to someone on the telephone, and they asked me as do most people these days How are you spelling the name? It always sounds as if they think I change my name every day and they would like to know how I am spelling it today. In any case I wasn't spelling it, I was saying it!
Why is the time honoured How do you spell your name, please?, only rarely used? It seems to be a more logical way of asking, since the way I spell it today is the same way I have been spelling it for decades - and I suppose that's the same with most people. It is also the way my eighteenth-century ancestors spelled it.
Is it perhaps that the latter sounds too direct a question to ask someone and how are you spelling seems less brusque and more polite. Or is it just a daft affectation that has caught on?