When a complex process (like design or science) is described in a model (like IDM or ISM) there is a tension between the conflicting criteria of simplicity and completeness. When a model is more complete it allows a more accurate description, but the resulting complexity can make the model less useful for education if students feel overwhelmed and confused because too many concepts are presented too quickly.
But this potential difficulty can be minimized — thus allowing a model to be used for teaching students of different ages and experience, abilities and interest — if the information content of the model is adjusted by simplification and enrichment. For example, in two pages (Introduction to Design and Overview of Design) IDM is described in two ways, using visual diagrams (shown below) and verbal descriptions that vary in detail, beginning with simplicity and building toward completeness and complexity.
