I used to live in Australia, so I've watched with great interest the Gillard-Rudd back and forth. I'm not sure if “tug of war” is a more apt analogy, or a “teeter-totter” or “push me pull you”. Anyway, one of those analogies works well for that, and that's just the Labour Party.
Professor, I did want to ask about something you said earlier, but just in passing. I think I'm characterizing what you said correctly, and this is why I'm asking the question. Under MMP it is possible to have electoral districts with significantly different populations for the purpose of better representation in rural areas, better connection for the MP and the riding, and then to have the list system even it out so that you still get a proportionate result. Is that in fact what you said?