About twenty years ago, some people were talking about role-playing on this thing called the "internet," and they had a really good idea. Not everyone liked role-playing for the same, distinct, unified reason. They used the word "style," and came up with Gamist, Simulationist, and Dramatist play, which they pretty much agreed couldn't be the same things.
In case you're interested, when I ran into this body of discussion, I changed the word "Dramatist" to "Narrativist" solely because Jonathan Tweet had already used "Drama" in the text of Everway to mean something else, a type of resolution. Plus, over time, I decided they were thoroughly right in the main point, that totally different ways to enjoy role-playing exist, but also that their categories were kind of muddled up. This wiki summarizes the discussion after that.
So give the Threefold Model a little respect.
A description of three distinct "styles" of role-playing, proposed by Mary Kuhner and further developed in on-line discussions. See John Kim's website for archives. The Threefold Model inspired but is not identical to the Creative Agenda feature of the Big Model.