  We give an in-depth analysis of the determination procedure of the recently
proposed heterotic nucleon distribution amplitude which hybridizes the best
features of the Chernyak-Ogloblin-Zhitnitsky and the Gari-Stefanis models. With
respect to the QCD sum-rule constraints, optimized versions of these amplitudes
are derived in terms of which a "hybridity" angle can be introduced to
systematically classify all models.
