It seems like it's originally an adventure-park ride in New Zealand, that they're now hoping to develop into public transport. It seems like a very strange idea to me, but who knows?
There is no need for an overtaking lane. When two riders come together, the dynamics change completely. Riders travelling separately are held back by the high pressure zone (the ‘headwind’) pushing against their nose, and the low pressure zone (the vacuum) pulling on their tail. When vehicles come together, these resistances are halved. The front rider loses their vacuum and the rear rider loses their headwind. In effect they become one vehicle with two engines. The front rider simply changes up a gear to compensate for the higher speed.
Just as tandem bicycles always travel faster than two single bicycles, two Shweebs travelling in a train always travel faster than either of them could travelling solo.
It is for this reason that the bullet shape is most efficient. Although an aerofoil (‘teardrop’) shape would be faster for a solo rider, its reduction of tail vacuum makes it less effective as a train segment.
Not all cities are flat. In locations where a Shweeb rail has to make a substantial climb upwards, a conveyor chain under the rail would lift the pods up the hill. This could be powered by solar panels on top of the rails and activated only when pods are travelling too slowly to clear the rise with their own momentum. Shweebs travelling faster than the speed of the chain would fly over it without being slowed.
