Interesting point, Jif. A search for the answer (with no D) produces nothing of value. With the D there are several occurrences of this as an adjectival phrase describing the individual in question. But neither appear to be an actual nickname (unless I've missed something). So is this not an example of the kind of non-standard multi-word phrase (such as "blue trousers" or "clever girl") which setters aren't really supposed to use?
Not that it bothers me much, as the answer was (quite) easy to get and the overall solving experience was fun.