  Contrary to widespread opinion, color transparency (CT) brings essential
ambiguity to, rather than helps in, study of the nuclear spectral function in
quasielastic lepton scattering, $A(l,l'p)A'$, at high $Q^2$. Although the
nuclear attenuation vanishes, the final state interaction (FSI) of a small-size
ejectile wave packet, propagating through nuclear matter, remains. It manifests
itself in a substantial, but uncertain, longitudinal momentum transfer to the
nuclear medium. We predict a strong Fermi-momentum bias of the nuclear
transparency at high $Q^2$, which enters as a factor at the nuclear spectral
function, and makes uncertain the results of measuring the high-momentum tail
of Fermi distribution.
