The Weisberger relation, an exact statement of the parton model, elegantly
relates a high-energy physics observable, the 1/x moment of parton distribution
functions, to a nonperturbative low-energy observable: the dependence of the
nucleon mass on the value of the quark mass or its corresponding quark
condensate. We show that contemporary fits to nucleon structure functions fail
to determine this 1/x moment; however, deeply virtual Compton scattering can be
described in terms of a novel F_{1/x}(t) form factor which illuminates this
physics. An analysis of exclusive photon-induced processes in terms of the
parton-nucleon scattering amplitude with Regge behavior reveals a failure of
the high Q^2 factorization of exclusive processes at low t in terms of the
Generalized Parton-Distribution Functions which has been widely believed to
hold in the past. We emphasize the need for more data for the DVCS process at
large t in future or upgraded facilities.Comment: 11 pages, 3 figures, invited contribution to the 11th International
Conference on Meson-Nucleon Physics and the Structure of the Nucleon, sept.
10th-14th 2007, Juelich, German