  We consider instanton contributions to chiral correlators, such as <0| Tr
\lambda^2 (x) Tr \lambda^2(x') |0>, in N=1 supersymmetric Yang-Mills theory
with either light adjoint or fundamental matter. Within the former model,
extraction of the gluino condensate from a connected 1-instanton diagram,
evaluated at strong coupling, can be contrasted with expectations from the
Seiberg-Witten solution perturbed to an N=1 vacuum. We observe a numerical
discrepancy, coinciding with that observed previously in N=1 SQCD. Moreover,
since knowledge of the vacuum structure is complete for softly broken N=2
Yang-Mills, this model serves as a counterexample to the hypothesis of Amati et
al. that 1-instanton calculations at strong coupling can be interpreted as
averaging over vacua. Within N=1 SQCD, we point out that the connected
contribution to the relevant correlators actually vanishes in the weakly
coupled Higgs phase, despite having a nonzero value through infra-red effects
when calculated in the unbroken phase.
