The innocuousness of adiabatic instabilities in coupled scalar
  field-dark matter models
  Non-minimally coupled scalar field models suffer of unstable growing modes at
the linear perturbation level. The nature of these instabilities depends on the
dynamical state of the scalar field. In particular in systems which admit
adiabatic solutions, large scale instabilities are suppressed by the slow-roll
dynamics of the field. Here we review these results and present a preliminary
likelihood data analysis suggesting that along adiabatic solutions coupled
models with coupling of order of gravitational strength can provide viable
cosmological scenarios satisfying constraints from SN Ia, CMB and large scale
structure data.
