Ideas or instantiations?

It is striking how the dichotomy between framework based approaches to managing projects vs. agile methodologies resembles the metaphysical discussion around Plato's theory of forms.
In Plato's opinion, forms / ideas are more real than their instantiations that we see in everyday life. The idea of a human being is more real than all the people you see around you every day.
Take this concept and apply it to framework based approaches such as CMMI. CMMI, we're being told, is a model, a framework for process improvement.
The point I'm trying to make is not that CMMI is more 'real' than any of its implementations / applications. It is that CMMI is a syntetic construct, just as an idea (in the Platonic sense). The problem is that, just like Plato's ideas, CMMI only sounds good when it is not applied. Once applied, it loses its universality, it's just faint shadows on the background of a cave. Thus, the framework itself is never to blame for inefficiencies or unnecessary processes. The framework is never the efficient cause of failure. The only blamable part is the implementation.
Agile on the other hand is a collection of disparate practices (what makes sense) collected during numerous project life cycles. The beauty of it is that, because these processes are already 'implementation', they are the cause of failure or, more often, project success.