Even if it became standard procedure to offset to one side of the track, in this particular incident as the A330 and A340 were both heading in the same direction they could have the same offset programmed and so the result would have been the same. As the overtaking aircraft was visual with the lower aircraft would it not be be a good idea, in this type of situation, to fly slightly right or left of track until past? Obviously may not be as easy under radar control.