Hello, for anyone looking at my recent posts on game design, there will be a bit of a delay before the next one.  It has nothing to do with the content -- I'm going through a bit of a family emergency right now.  My polan was to post a discussion Domain Interaction up sometime in April.  The interactions are the part of the model that makes predictions, making them one of the most important aspects of the model.  However, this is the most volitile and (currently) subjective area, so I might go with Standard Domains first, which are easier to scope, but are largely a toolset for quickly describing systems in your game.