  We obtain general analytical forms for the solutions of the one-loop
renormalization group equations in the top/bottom/$\tau$ sector of the MSSM.
These solutions are valid for any value of $\tan \beta$ as well as any
non-universal initial conditions for the soft SUSY breaking parameters and
non-unification of the Yukawa couplings. We establish analytically a generic
screening effect of non-universality, in the vicinity of the infrared quasi
fixed point, which allows to determine sector-wise a hierarchy of sensitivity
to initial conditions. We give also various numerical illustrations of this
effect away from the quasi fixed point and assess the sensitivity of the Higgs
and sfermion spectra to the non-universality of the various soft breaking
sectors. As a by-product, a typical anomaly-mediated non-universality of the
gaugino sector would have marginal influence on the scalar spectrum.
