Is 4d actually in Chambers at all? I think I've got it right - it parses, as do the crossers, and I've found references to it being a nickname for a Prince of Wales - but when I can't find it in the big red book (13th), I get nervous.
I think that Azed is viewing it as a proper name (thus not requiring individual mention) given that it was specifically the nickname of the future George IV.