[Patrick_Devine]

Except, not really, right? If you mean at existing service levels, then yes, of course. It's not really worth it.

Where automation really helps though is with _frequency_ of trains. If you have headways which are half as long (like in Vancouver on the Expo line the headways are every 90 seconds during peak periods) it makes a huge difference compared to something like SF's BART which has a weekday frequency of 15 minutes.

It also makes a massive difference when you're building a new line. If you can half the headway, you can half the size of the platform which makes building the line considerably cheaper. Less land to appropriate, less concrete to pour, less land to dig, etc.

There is one problem though. If you build a super convenient metro system with trains every minute or two, people will start to use that system. A lot. Vancouver's system is running into problems (particularly on the Canada Line) with massive overcrowding because even with the high frequency of trains, there's just not enough capacity.

[jnty]

As the article says, many metros (including the one in the article) combine automation with drivers. You only need to pay for the bit of automation that actually increases frequency and use the driver for all the fiddly bits.