  We provide a theorem to suggest that $t=0$ data may already be sufficient to
detect possible asymptotic C-odd (Odderon) contributions. This can be done by
comparing $\bar p p$ and $pp$ $t=0$ observables such as total cross sections,
forward angular distributions and ratios of real to imaginary forward
amplitudes for which well defined model independent correlations {must} exist
which could already show up at RHIC energy but definitely at LHC energies.
