Rider-training courses commonly describe a single traffic lane as three notional tracks — left, centre and right. Why is that a useful way for a motorcyclist to think about lane position?

1. To allow three motorcycles to race side-by-side in one lane
2. To allow the rider to adjust positioning for optimal visibility, sightlines, hazard avoidance, and escape paths
3. Because the GDT requires riders to switch positions every 10 seconds
4. To share the lane with passenger cars abreast