It was around 7:40am on May 5, 2017, when driver Oliver Salbris pulled the number 430 bus out from stop FE on Putney Bridge, heading south. Traffic is slow in South West London at that time of day and he couldn’t have been doing more than around 12mph. If the bus had been moving any faster then things might have played out differently. One minute, the road was clear. The next, a woman was falling...