I looked hither and yon for the etymology of "Molly Hogan." It appears quite a few people are familiar with the name but not its origin. The closest bit I found, from Heavy Equipment Forums, and I don't know if it's true, is this: "Why Molly Hogan? It was explained to me that Molly was the daughter of the boss and she was shall we say very friendly to the crew. A quick and temporary connection." http://www.heavyequipmentforums.com/threads/history-gurus-who-invented-the-haulback.24216/