Found a marvelous track schematic of the approaches to Boston's South Station I am currently boggling at the tower 1 messpic.twitter.com/RzBq9eiTNv
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I assume the reason is they can't turn trains around fast enough to allow dedicated platforms for different approaches, but I'm not sure
Thinking of high-freq stub-end lines in Tokyo, like the Chuo Rapid--it has two approach tracks and two tracks (one platform) at the terminal
That's sufficient for trains coming and going every few minutes--but only because no other line's tracks are creating traffic conflicts
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