  The shape of the surface brightness profile of dE galaxies, quantified by
parameter n of Sersic's generalized profile law, has recently been put forward
as new extragalactic distance indicator (Young & Currie 1994). Its application
to the Virgo cluster has subsequently led to the claim that the Virgo dEs are
not lying in the cluster core but are distributed in a prolate structure
stretching from 8 to 20 Mpc distance (Young & Currie 1995). This claim is
refuted here. We have fitted a Sersic law to the surface brightness profiles of
128 Virgo cluster dEs and dS0s from the photometry of Binggeli & Cameron
(1991). The dispersion of the n-M relation is indeed large. However, we argue
that this scatter is not due to the depth of the Virgo cluster, but is
essentially intrinsic. Contrary to what one would expect from the cluster depth
hypothesis, there is no clear velocity-``distance'' relation for a sample of 43
Virgo dEs and dS0s with known redshifts. The analysis of Young & Currie (1995)
is hampered by the use of low-resolution photometry and flawed by the
assumption that the n-M and n-R relations can be used independently. By
combining different Sersic law parameters, the scatter of the scaling relations
can be reduced somewhat, but never below sigma_{rms} approx 0.7 mag, at least
for the Virgo cluster. For the purpose of distance measurements, this is
comparable to what one can get already from the <mu>_{eff}-M relation for dEs,
which does not require any profile modelling.
