The ears localize sound sources by two mechanisms: Arrival time and intensity. If the arrival times of the two speakers are not simultaneous, good soundstaging can be maintained by correspondingly increasing the intensity (loudness) of the farther speaker. So to answer the original question, yes it's perfectly legitimate to use the balance control to offset the effects of having one speaker closer than the other. The results won't be perfect, but they'll be better than if you do nothing about the difference in arrival times.
Duke
dealer/manufacturer
Duke
dealer/manufacturer