  Miraculously, target mass corrections for inclusive deep inelastic scattering
can be calculated exactly. On the contrary, there does not exist a consistent
derivation of kinematic hadron mass corrections for semi-inclusive deep
inelastic scattering (SIDIS). Recently this has become of topical interest,
since there is a significant difference between the measured HERMES and COMPASS
pion and kaon multiplicities, which cannot be explained as a consequence of
evolution in $Q^2$, and it has been suggested that the difference can be
understood if kinematic hadron mass corrections are taken into account. We
explain why this argument is incorrect.
