  We study implications of a model, which links nuclear and nucleon structure
functions. Computed Callen-Gross functions $\kappa^A(x,Q^2)=
2xF_1^A(x,Q^2)/F_2^A(x,Q^2)$ appear for finite $Q^2$ to be close to their
asymptotic value 1. Using those $\kappa$, we compure $R$ ratios for $Q^2\ge 5
GeV^2$. We review approximate methods in use for the extraction of $R$ from
inclusive scattering and ENC data. Further we calcuate ratios of the moments of
$F_k$ and find these to describe the data, in particular their $Q^2$
dependence. The above observables, as well as inclusive cross sections, are
sensitive tests for the underlying relation between nucleonic and nuclear
structure functions. In view of the overall agreement, we speculate that the
above relation effectively circumvents a QCD calculation.
