What do the conditions of exact pseudospin symmetry in nuclear relativistic models mean in real nuclei?

We study the continuous evolution of the single-particle levels from a model satisfying exact spin symmetry (SS) to another one satisfying exact pseudospin symmetry (PSS), using a Dirac equation with potentials of scalar, vector and tensor type. All the standard pseudospin doublets (PSDs) appearing in the limit of the SS have their corresponding PSDs in the limit of the PSS but not vice versa. The PSS is strongly violated between the SS and PSS limits