  Recently, Jaeger and Willenbrock have shown that the Appelquist and Chanowitz
bound on the scale of top-quark mass generation can formally be saturated in a
particular limit of a two-Higgs doublet model. In this note I present an
alternate derivation of their result. I perform a coupled channel analysis for
f fbar to V_L V_L and V_L V_L to V_L V_L scattering and derive the conditions
on the parameters required for f fbar to V_L V_L scattering to be relevant to
unitarity. I also show that it is not possible to saturate the bound on fermion
mass generation in the two-Higgs model while maintaining tree-level unitarity
in Higgs scattering at high energies.
