In the early 1950s I owned a textbook written by & for pacifists about how to go to prison (not a dull page in it). It referred to tales of prisoners' wives' unfaithfulness as "`Joe, the grinder' stories". I have often wondered if "Joe the grinder" was not the original name of the character, and "Jody Grinder" a corruption of it. In some dialects they would be pronounced about the same.