Left: same gridding in inclination ζ and magnetic inclination α as in the Atlas of gamma-ray profile shapes of Romani & Watters (Fig. 15, 2010). The occupancy fractions assume uniform distributions in α and cosζ. Right: fraction of simulated lightcurves exceeding 4σ with the H-test, as a function of pulsar flux above 100 MeV, for a fixed background intensity, for different profile shapes. w is the gap width defined in the text.