sentences:  Even though this did not make the trains one-man operated - seeing as the trains were still manned with a guard - it was one of the first steps towards it.Besides the dead man's switch, the electrification and dieselisation of railways also helped reduce the required staff in the locomotive to a sole operator - as diesel and electric traction does not require a fireman to shovel coal into a boiler.On the London Underground, the use of multiple units ended the need for a second crewman in the motorman's cab to assist with coupling at the terminal train station.