In a data handling system having a radially-dependent track incongruity
between data surfaces, at least some tracks are logically mapped so that
tracks on different data surfaces correspond with one another. The
correspondence is defined by the mapping so as to shorten an average
headswitch seek. For example, a logical track mapping of first and second
non-coaxial track sets can be defined so as to optimize a headswitch seek
within each of many intermediate logical cylinders identified in the
mapping.