The extra boxes complicate traditional velocity scanning. Many programs ignore it without embarrassment only because low-velocity events contain only shallow information about the earth. A significant improvement is made by summing all the points in boxes. A second concern arises from the sampling in velocity space. Traditionally people question whether to sample velocity uniformly in velocity, slowness, or slowness squared.
Difficulty arises first on the widest-offset trace.
Too large an interval in velocity will leave a gap between the hyperbolic scans. With the new method there is no chance of missing a point on the wide-offset trace. Also, the inner trace enters only once. The new method also makes many old interpolation issues irrelevant. New questions arise, however.