Darcy gave him a little nod of appreciation, and then ventured to explain his difficulty with names.
"I appreciate that. It's a strange familiarity to get used to. I have a cousin - he's a colonel, I call him Colonel, or Colonel Fitzwilliam - which is his surname, although it is my first name, just to make it even more ridiculous," he made a bit of a face, and waved this side comment away. "Anyway, we have been near enough brothers since childhood, and still he is Colonel, and I am Darcy. First names are used so rarely they are almost irrelevant," he explained. "But if it makes you more comfortable, I will try."