We compute the renormalization of dimension six Higgs-gauge boson operators
that can modify \Gamma(h -> \gamma \gamma) at tree-level. Operator mixing is
shown to lead to an important modification of new physics effects which has
been neglected in past calculations. We also find that the usual formula for
the S oblique parameter contribution of these Higgs-gauge boson operators needs
additional terms to be consistent with renormalization group evolution. We
study the implications of our results for Higgs phenomenology and for new
physics models which attempt to explain a deviation in \Gamma(h -> \gamma
\gamma). We derive a new relation between the S parameter and the \Gamma(h ->
\gamma \gamma) and \Gamma(h ->Z \gamma) decay rates.Comment: 20 pp. 2 fi