[trainyperson]

Much of what you’re describing (besides the live hitching and unhitching) is made possible by Communication-Based Train Control (CBTC) [see link below]. This has been implemented in many rail systems globally, mostly urban rail. It helps reduce headways a lot. However:

1. It’s not just a software problem - installing the hardware is time-consuming and expensive. The engineering requirements are much stricter when human lives are at stake so you can’t just strap on a radio to each train. You still need additional infrastructure along the tracks to manage communications.

2. There are other limiting factors in reducing headway - having enough trains and having enough train operators. Somewhat easier to solve perhaps but still costly and non-trivial.

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https://en.wikipedia.org/wiki/Communications-based_train_con...

[TylerE]

Urban systems are generally single-user networks, which makes life a lot easier. For main line railways that assumption doesn't hold, which is where things kinda fall apart.

It's a bit like the old copypasta from the slashdot days of "This is why your solution to spam won't work", where one of the options was "It requires the entire internet to change at once.

Just look at what a big deal in the US it was to get positive train control (PTC) installed nationally.. and that's a much simpler system that is basically local (Picks up info from relays in the track, but all the logic is in the locomotive).