Rail gives you more capacity. Of course if you don't need that capacity then the value proposition is questionable: perhaps better to start with a BRT and try to get things to grow.
BRT would be a good (and cheap) upgrade for a lot of the absurdly wide stroads covering US cities. Bonus points if you can get the intersections on those roads converted to roundabouts. The whole reason why those stroads got so comically wide is so that all the cars have somewhere to park while they're waiting for the next light. Roundabouts are continuous flow and can handle a lot more traffic than a signaled intersection, so you can take out the center lanes in favor of dedicated bus infrastructure.
The reason why most buses suck to take is because they can never keep to a schedule when they're sharing the same lanes that private cars take, have to wait at the same lights as them, etc.
>The reason why most buses suck to take is because they can never keep to a schedule when they're sharing the same lanes that private cars take, have to wait at the same lights as them, etc.
They're also pretty damn uncomfortable to sit on: bouncing motions, herky-jerky steering motions, etc. Compare that to sitting on a subway car: the subway is FAR more comfortable because it's riding on rails and doesn't bounce around a lot. And if it's really crowded, it's a lot easier to stand up while riding a subway than a bus.
A single-lane BRT can carry 9000 people, while a single-lane streetcar/tram/LRT can carry 18000:
* https://en.wikipedia.org/wiki/File:Passenger_Capacity_of_dif...
* https://en.wikipedia.org/wiki/Route_capacity
Rail gives you more capacity. Of course if you don't need that capacity then the value proposition is questionable: perhaps better to start with a BRT and try to get things to grow.