  Knowing whether a hadron is formed inside or outside the nuclear medium is
very important for correctly interpreting jet quenching in heavy-ion
collisions. The cleanest experimental environment to study the space-time
evolution of hadronization is semi-inclusive DIS on nuclear targets. Two
frameworks are presently competing to explain the observed attenuation of
hadron production: quark energy loss, with hadron formation outside the
nucleus, and nuclear absorption with hadronization starting inside the nucleus.
I demonstrate that the observed approximate A^(2/3) scaling of experimental
data cannot conclusively establish the correctness of either energy loss or
absorption.
