It is possible for a representation strategy to include both commonality and variability across systems, but to not differentiate which part of the model is which. Therefore in our final version of the Kiviat diagrams we called out as a feature the extent to which a given representation strategy differentiates between commonality and variability. (This is an example of partial dependencies across the features: e.g., if a representation only describes commonality, then the question of differentiation is moot.)
Differentation of inter- and intra-system attributes is closely related to this feature.