  We show how to renormalize chiral two pion exchange perturbatively if one
pion exchange has already been fully iterated at leading order. This particular
choice corresponds to the implementation of the counting proposal of Nogga,
Timmermans and van Kolck at subleading orders. We illustrate why the
perturbative treatment of the two pion exchange contributions is mandatory in
order to avoid certain inconsistencies in Weinberg's counting. In addition,
renormalizability implies modifications of the power counting which we explore
for the particular case of the singlet channel.
