Why should motorcycle riders generally avoid riding in the centre third of a traffic lane, especially when approaching intersections?

1. The centre strip accumulates leaked engine oil, transmission fluids, and coolant from cars, making it extremely slick when wet or braking
2. The centre strip is where road cambers drain, so it is always the wettest part of the lane
3. Riding centrally is illegal on any road with lane markings
4. The centre gives the poorest view of the road ahead