  A way of testing the $\pi \pi$ predictions of Chiral Perturbation Theory
against experimental data is to use dispersion relations to continue
experimental information into the subthreshold region where the theory should
unambiguously apply. Chell and Olsson have proposed a test of the subthreshold
behaviour of chiral expansions which highlights potential differences between
the Standard and the Generalized forms of the theory. We illustrate how, with
current experimental uncertainties, data cannot distinguish between these
particular {\em discriminatory} coefficients despite their sensitivity.
Nevertheless, the Chell--Olsson test does provide a consistency check of the
chiral expansion, requiring that the ${\cal O}(p^6)$ corrections to the {\em
discriminatory} coefficients in the Standard theory must be $\sim 100%$.
Indeed, some of these have been deduced from the new ${\cal O}(p^6)$
computations and found to give such large corrections. One can then check that
the ${\cal O}(p^8)$ corrections must be much smaller. We conclude that this
test, like others, cannot distinguish between the different forms of Chiral
Symmetry Breaking embodied in the alternative versions of Chiral Perturbation
Theory without much more precise experimental information near threshold.
