Some discussion elsewhere on the etiquette of filtering to the front at traffic at lights and keeping clear of pedestrian crossing areas. allowing following filtering motorcycles access to the front row staying out of bicycle Advance stop line boxes. made me remember this 2013 UK study on allowing motorcycles to share bicycle stop points. The UK study showed benefits and broad agreement from the motorcycling and bicycling communities in the UK. I don't believe it has been adopted as law there yet though. Whether there would be as great a support from the bicycle community here is less certain considering their response to sharing bicycle lanes with motorcycles.