Consistency of Relevant Cosmological Deformations on all Scales
  Using cosmological perturbation theory we show that the most relevant defor-
mation of gravity is consistent at the linear level. In particular, we prove
the absence of uni- tarity violating negative norm states in the weak coupling
regime from sub- to super-Hubble scales. This demonstrates that the recently
proposed classical self-protection mechanism of deformed gravity extends to the
entire kinematical domain.
