One of the challenging things I saw in the article we read was the need for students to connect models to explanations. I think it could be very easy to have students model an event or process and revise it, but them to not be able to explain their models in the end. It could end up being like trying to teach students the physics concepts of falling motion by only having them play Angry Birds - some students would get something out of it, many would not, and even those that did may not be able to articulate the concepts accurately.
To that end, I think that it's important for us as teachers to consistently be pushing students to develop explanations using their model. If we simply push them to make a model, we may not be developing deep understanding of concepts in our students. This is why I think that the middle day of model revision, adding to explanations, and critiquing each other's models is so important to the learning sequence. It allows the teacher and fellow students the opportunity to push students to think about explaining the unobserved rules behind the observed phenomena.