  Central production cross-sections of hard dijets with 2,1 or 0 rapidity gap
at Tevatron are analyzed in terms of diffractive (``a la Good-Walker'') and non
diffractive fluctuations of the incident particles. The observed large
factorization breaking and the unexpected high value of the 2 to 1 gap
cross-section ratio are explained in terms of scattering with and between the
incident particles.
