I wonder if this savings includes the additional time to walk further to a stop.
Especially in light of this quote:
> In England, where 28 percent of all bus passengers are on concessionary fares for age or disability
Humans walk at roughly 2.1-3.0mph. "European cities" are listed as having bus stops 984-1476 ft apart, which would imply you'd typically walk half that to reach the nearest one (492-738 ft), which for a fit 3.0mph person is 2-3 minutes, and for a frail old 2.1mph person is 3-4 minutes.
Of course, people can be further away than that (they live orthagonally to the bus route), but you get the point. If you doubled bus stop distances to 1476ft apart, it would not add many walking minutes for the users.
Bus users can compensate for extra walking time by leaving earlier, provided the bus is on time. Good bus services can estimate arrivals in realtime, and show it to users on websites, apps, etc. as well as at the bus stop.
Bus punctuality is affected by a number of factors (e.g. traffic congestion, temporary and dedicated bus lanes), including number of stops.
The faster a bus can complete its route, the higher the route frequency can be with the same number of buses+drivers, which means buses pick up passengers more often, which means fewer passengers per stop (because less time between pickups), which means faster boarding, which in turn allows for a higher reliable route frequency. Having payment schemes like tap on/tap off, and having multiple entry doors also improves boarding times.
> Humans walk at roughly 2.1-3.0mph. "European cities" are listed as having bus stops 984-1476 ft apart, which would imply you'd typically walk half that to reach the nearest one (492-738 ft), which for a fit 3.0mph person is 2-3 minutes, and for a frail old 2.1mph person is 3-4 minutes.
> Of course, people can be further away than that (they live orthagonally to the bus route), but you get the point. If you doubled bus stop distances to 1476ft apart, it would not add many walking minutes for the users.
Given four "bus stops" spaced at the corners of a square of dimension d, and a linear relationship of distance and time such that d == t, the distance to a stop along the edges of the square is at most d/2 == 0.5d. As the crow flies (straight line) the distance from the center of the square to any of the corners is sqrt(2*(d^2)) / 2 or (approximately) 0.71d.
But people don't fly, rather geometric physical reality is something sometimes called "manhattan distance" which essentially means that they need to walk to the edge and then along the edge (or zig-zag block by block, which amounts to the same thing just repeated at smaller scale). In this case the distance walked to any of the corners from the center is exactly d. Unless you live in the middle of a park (with stops at the corners) d is the best outcome. In a physical environment other obstacles may present which require backtracking; indeed, the bus routes (and hence stops) are likely optimized to avoid backtracking, acknowledging this physical reality.
And that doesn't even consider that a faster bus route means you need fewer buses to run the same number of trips, so you can either run more trips (and save even more time for riders waiting for their bus) or cut down costs for the transit operator.
One can calculate how much area and thus passengers the stop covers and calculate walking times.
It's not completely trivial (with longer distance people chose alternatives), but can be done similar to the way the whole study was done with similar accuracy.