  We consider N=1 supersymmetric U(N), SO(N), and Sp(N) gauge theories, with
two-index tensor matter and added tree-level superpotential, for general
breaking patterns of the gauge group. By considering the string theory
realization and geometric transitions, we clarify when glueball superfields
should be included and extremized, or rather set to zero; this issue arises for
unbroken group factors of low rank. The string theory results, which are
equivalent to those of the matrix model, refer to a particular UV completion of
the gauge theory, which could differ from conventional gauge theory results by
residual instanton effects. Often, however, these effects exhibit miraculous
cancellations, and the string theory or matrix model results end up agreeing
with standard gauge theory. In particular, these string theory considerations
explain and remove some apparent discrepancies between gauge theories and
matrix models in the literature.
