It would add some variety to the same service. It could work by adding an option in the menu to toggle on/off then if it's enabled a service ahead of the player train could be delayed by a small amount to make the drive a bit more of a challenge. When it's enabled in settings it wouldn't always give you a delay but it would be random, if there was a delay then when entering a service, and once spawned in the cab a message could appear letting the player know that there may be some delay to the journey.
