  A charged lepton contribution to the solar neutrino mixing induces a
contribution to theta_13, barring cancellations/correlations, which is
independent of the model building options in the neutrino sector. We illustrate
two robust arguments for that contribution to be within the expected
sensitivity of high intensity neutrino beam experiments. We find that the case
in which the neutrino sector gives rise to a maximal solar angle (the natural
situation if the hierarchy is inverse) leads to a theta_13 close to or
exceeding the experimental bound depending on the precise values of theta_12,
theta_23, an unknown phase and possible additional contributions. We finally
discuss the possibility that the solar angle originates predominantly in the
charged lepton sector. We find that the construction of a model of this sort is
more complicated. We comment on a recent example of natural model of this type.
