The patient does not feel like the center. It is all about Experience. In agile terms "User Experience". If the user does not feel the experience they want, then they are NOT happy. Does not matter how hard the product is trying to make the user happy. If hey are not feeling it, then they are not happy.
I assert this is NOT because of the architecture of Health Information Exchanges. BUT rather that this is because of a lack of considering how the would or could Patient Experience the impact available because of the Health Information Exchange. The architecture supports the following Patient Centered use-cases.
Lets think about the Patient -- User Experience. I offer the Privacy Principles as the use-case to drive this User Experience. You can certainly also consider healthcare treatment use-cases, I won't simply because I am not an expert there. I do fully expect that Care Plans covering chronic care conditions will be the killer-app (sorry) for Health Information Exchanges.