Actually reading the article, I think the most interesting part of it is not the one-party democracy or even the insights it provides about Japanese politics. I

Actually reading the article, I think the most interesting part of it is not the one-party democracy or even the insights it provides about Japanese politics. It is the fact that they did something that is generally discouraged in this field: using open-ended questionnaires. And it gave them tons of insights! Instead of asking "Which party do you prefer?" They realized that almost no party preference was expressed, except for the LDP, the ruling party and usually as an opposition to it. They discovered the categories of focus in the electorate instead of shoehorning a grid into it. Of course you don't really want to do it when you compare countries, and you open yourself to a ton of bias when you do manual analysis, but I think it is good once in a while to do such a thing to allows insights that may have been missed to show up.