Cognitive models of software comprehension are potential sources of
theoretical knowledge for tool designers.  Although their use in analysis
of existing tools is fairly well-established, the literature has shown only
limited use of such models for directly developing design ideas.  This
paper suggests a way of utilizing existing cognitive models of software
comprehension to generate design goals and suggest design strategies early
in the development cycle.  A crucial part of our method is a scheme for
explaining the value of tool features by describing the mechanisms that are
presumed to underly the expected improvements in task performance.