  The addition of a topologically massive term to an admittedly non-unitary
three-dimensional massive model, be it an electromagnetic system or a
gravitational one, does not cure its non-unitarity. What about the enlargement
of avowedly unitary massive models by way of a topologically massive term? The
electromagnetic models remain unitary after the topological augmentation but,
surprisingly enough, the gravitational ones have their unitarity spoiled. Here
we analyze these issues and present the explanation why unitary massive
gravitational models, unlike unitary massive electromagnetic ones, cannot
coexist from the viewpoint of unitarity with topologically massive terms. We
also discuss the novel features of the three-term effective field models that
are gauge-invariant.
