Well going by that dudi no matter where they are (bike, bus, taxi or even walking) they are going to course some thing to happen. As you say "think of some pisshead hurtling down a steep hill on a bike" I do not think that will happen if they can not even walk staight As you say "now think of them staggering down the path". We can apply if this, if that, what about this, what about that, To anything we do like bikes and bus's being on the same road and bike's shearing a cycle lane with people..... There is danger all over the place not just from people that have had a bit to much to drink.