The problem with any theory of modified gravity is that there is just no physical justification for it. It's only motivation seems to be to explain away dark matter by adding and tweaking free parameters until you fit the data, which you can always do given enough variables.
van Neumann's quote comes to mind - "With four parameters I can fit an elephant, and with five I can make him wiggle his trunk."
van Neumann's quote comes to mind - "With four parameters I can fit an elephant, and with five I can make him wiggle his trunk."