  The idea that mergers are more likely in dense groups or clusters coupled
with the assumption that such events lead to cold gas flows onto black holes,
suggests a direct relationship between the radiative efficiency of an active
galactic nucleus and environmental richness. Observations, however,
increasingly challenge this and other basic expectations. Mounting evidence,
for example, shows an inverse trend between near-Eddington accreting objects
and environmental richness. Broken down by radio galaxy subgroup, recent work
has explored connections between low excitation radio galaxies with
Fanaroff-Riley II jet morphology (FRII LERGs) and other radio galaxies. We make
contact with that work by adding a discussion of the recently discovered FR0
radio galaxies and show how to fit them in a picture in which FRII LERGs are
not initial nor final phases in the lifetime of a radio galaxy, but de facto
transition states. We describe how to understand the observed X-ray
luminosity/cluster richness relation as a fundamental correlation on the nature
of the jet-disk connection.
