A therapeutic neurostimulation system configured for providing therapy to a patient. The neurostimulation system comprises a neurostimulation lead having an array of electrodes arranged along a longitudinal axis configured for being implanted along a spinal cord of a patient, a neurostimulation device configured for delivering electrical stimulation energy to active ones of the electrode array, and control/processing circuitry for instructing the neurostimulation device to configure an active electrode as a cathode, and two active electrodes longitudinally flanking and laterally offset from the cathode as anodes, selecting a ratio of stimulation amplitude values for the two anodes based on a known longitudinal location of the implanted neurostimulation lead relative to the spinal cord, and instructing the neurostimulation device to distribute the electrical stimulation energy between the two anodes in accordance with the selected stimulation amplitude value ratio.