When Chicago got rid of the conductors, trains got slower and less reliable. If you've ever had to wait on the train while the operator has to come out of the cab to help a disabled person, respond to a door fault or call button, you've been delayed by one man train operation.
In fact every time the train stops and there's a noticable pause before the door opens, that is caused by the operator having to move from the driving controls to the door controls.
Same. The only time the operator leaves the cabin where I live is when they're switching which end of the train they're driving from or they're taking the train out of service at the last stop. There's almost no other reason for them to ever do so.
We haven't had a derailment here since 2009 where a train left the track by about a foot or so. It could happen, but in the course of normal business operations, evacuations are not a regular event here pulling operators out of their cabins. More likely is a door breaks (or rather someone breaks a door) and they have to seal it manually to keep the train moving, but I only see that happen on the older >20 years old stock and pretty much never on the newer stock.
I’ve not had any of that on the London Underground which hasn’t had a second operator for 25 years. No delays in DOO above trains - at least not the kind that a separate guard would solve.
The major impact is at stations without level boarding where assistance which should be from the platform doesn’t arrive.
One could simply just buy trains that have door controls and driving controls in the same ergonomic layout. Other places have OPTO without these problems.
In fact every time the train stops and there's a noticable pause before the door opens, that is caused by the operator having to move from the driving controls to the door controls.