Funny you should mention scrutable learner models: In Denmark I will be working with a large team that includes Susan Bull (a close colleague of Judy Kay's -- with luck we'll manage to get some of her attention too) and we will be focusing on Open Learner Modelling. My contribution to the project will be the implementation of a communication and negotiation layer to communicate the learner models to the interested parties (students, teachers, administrators, parents, etc.). The big challenge, as you rightly point out, is how to communicate the model of a complex thing (the learner model in this case) without using a complex representation. I hope we'll take up some issues around representations of complex entities in Week 4 with tools like Gephi.