The parameter block was introduced in this work without giving a lot of detail as to what exactly the high level entities represent.
Third level entities, where meta-level knowledge about the design is supposed to reside, were not defined in specific terms. It is not very clear what, or in what form, the information should be stored in the third level criticisms, praises, and evaluations in order to help the design process. More work is needed to formalize the contents of the third level entities.
Although the entities with levels of reference higher than three are possible in our model of the parameter block, more research needs to be done concerning these entities. Are these entities meaningful in the context of design? If so, what role do they play and what knowledge can be stored in these entities? Does this knowledge help the design problem solving in any way?