Indeed and I have a vauge memory of a legend about a Thief that was known as "Gentleman [something]".
So it's probably a very used term for a great and known Thief.
Only if said thief wears a "rosetted" pony tail, cravat, and pastel-coloured clothes :dance:
Of course, he could for the more strict, down-played 19-century style as well, but then he would also have to abandon decadency for manners, and what fun is that?