  Analyticity constitutes a rigid constraint on hadron scattering amplitudes.
This property is used to relate models in different energy regimes. Using meson
photoproduction as a benchmark, we show how to test contemporary low energy
models directly against high energy data. This method pinpoints deficiencies of
the models and treads a path to further improvement. The implementation of this
technique enables one to produce more stable and reliable partial waves for
future use in hadron spectroscopy and new physics searches.
