  We comment on the nature of the ordering transition of a model of equilibrium
polydisperse rigid rods, on the square lattice, which is reported by Lopez et
al. to exhibit random percolation criticality in the canonical ensemble, in
sharp contrast to (i) our results of Ising criticality for the same model in
the grand canonical ensemble [Phys. Rev. E 82, 061117 (2010)] and (ii) the
absence of exponent(s) renormalization for constrained systems with logarithmic
specific heat anomalies predicted on very general grounds by Fisher [M.E.
Fisher, Phys. Rev. 176, 257 (1968)].
