This is one of these issues where the public can understand when there is the same practice in the same type of train, with similar staffing, across all TOCs. What seems impossible to justify is different practices between TOCs or different practices between depots.
I agree. All the rulebook requires is that the crew satisfy themselves that the train is correctly platformed. In most locations this can be done from the doorway. However many operators have gold-plated this and require their guards to physically step onto the platform, so that they have been
seen to check. It's a performance for the CCTV.
Don't modern trains have a facility to automatically keep the doors on the rear carriage from opening at certain stations with a short platform? Can't the same system be used to prevent driver error?
For a price. Some units use balises to know precisely which doors are platformed. The cheaper form of ASDO on the other hand just knows how many doors
should be platformed at a given station, it has no idea if the driver has actually stopped at the four car mark or the two car mark. It just goes "three coaches should be platformed here, so I'll open three coaches" even though the driver has stopped short and one of those coaches is off of the platform.
Given the reliability of Northern's units the driver's probably worried about the doors being jammed and the service being terminated short when the guard doesn't appear.
More likely to be concerned that the guard may have been thumped.
If that is the case, then Northern need a few meetings with some of the DOO operators to see how they manage to stop in the right place...
In the case of Burnham (Bucks) by sticking all of the car stop marks right down the far end of the platform, leaving passengers with a very long walk from the entrance when a two car Turbo is diagrammed.
Is it any worse than trying to get to the door controls on a packed 156 or 158?
The door controls on each side of a 15x unit are (sensibly) located next to each other. You don't have to elbow your way through the length of the saloon for the one on the opposite side between Oxford Road and Piccadilly.
So does the guard starting the door release process, prevent the driver from moving the train forward if the signal goes green? I don't think the driver is going to wait for a signal from the guard if it's not scheduled to stop there. I wasn't thinking about it being an issue for a passenger to alight on to a platform. I was thinking more of the guard being left behind and a set of doors open as the train moves on to Oxford Road station.
On any multiple units in service today the door circuits are interlocked with the brakes. In the days of slam door stock with no traction/brake interlock it was necessary to give the tip to start away from a station if stopped out of course.