Station dwell times can have a big effect on the overall performance of a railway, especially a busy commuter routes. The old slam door trains had doors spaced two metres apart, which made for fast boarding and alighting, and passengers used the open doors to provide support over the gap between the platform and the train. Much of Britain's railway system was built when railway carriages were under ten metres long, which meant that there was never much of a gap even at sharply curved platforms. In combination with the high platforms that were standard in Britain, getting on and off trains was easy. But nowadays, carriages are twenty metres long or more, which means there can be a significant gap. Worse still, the tracks are now more sharply tilted on curves to allow for higher speeds. This leads to the situation here at Clapham Junction, where there is a huge gap between the platform and the train. Apart from being a danger, passengers take extra care and extra time to get on and o...