The details of the different processing stages is not the subject of the present paper. That is an issue to be addressed by other models that choose to delve deeper into the details of perceptual processing. Models of visual computation can be validly presented at different levels of specificity. In this model I have chosen to address the more general issue of how a hierarchical architecture (any hierarchical architecture) can be resolved with the Gestalt principle of emergence to account for the reification plainly evident in Gestalt phenomena. This point is made clear several times in the paper.
The justification for the particular stages of processing is indeed derrived from other models, which reflect the commonly held view of a hierarchical organization in the visual system with a progressive abstraction bottom-up from level to level. I could just as well have discussed this concept in the abstract, without providing specific examples. However I happen to believe that abstract concepts are very much clarified when presented with specific examples. The exemplary intent of these demonstrations is explicitly stated in numerous places throughout the paper.
As to the applicability of the model, it is by no means limited by its generality, rather its implications are broader, because instead of applying only to a narrow class of models for which it is demonstrated, it applies to any model of vision that suggest a hierarchical representation of lower and higher levels. This happens to be a widely held paradigmatic assumption of cortical organization. The fact is that there continues to be considerable debate in the literature over which stages of cortical processing "precede" or "succede" which other stages of processing, i.e. which cortical regions serve as input to other regions "downstream" in the hierarchy. I propose here that those distinctions are irrelevant, because the different cortical levels, while still hierarchical in nature, perform a parallel computational function in which no level should be considered to "precede" or "succeed" any other. This is a novel conceptual approach to an important issue that deserves to be exposed to the wider community.