  The goal of this work is to investigate under which circumstances the tidal
response of a stratified body can be approximated by that of a homogeneous
body. We show that any multilayered planet model can be approximated by a
homogeneous body, with the same dissipation of tidal energy as a function of
the excitation frequency, as long as the rheology of the homogeneous model is
sufficiently complex. Moreover we provide two straightforward methods for
finding the parameters of the homogeneous rheology that would exhibit the same
tidal response as the layered body. These results highlight the fact that the
two models cannot be distinguished from each other only by the measurement of
the second degree tidal Love number and quality factor, and that we do not need
the complexity of the multilayer planet model in order to estimate its tidal
dissipation. The methodology promises a great simplification of the treatment
of multilayered bodies in numerical simulations because the treatment of a
homogeneous body -- even with a complex rheological model -- can be
computationally better handled than that of a multilayered planet.
