Hmm, reading the article, it sounds to me like there's still a schedule. But instead of it being based on a set time, it's more like "The busses should try to keep a 2 km distance to each other at all times" (purely imaginary/exemplary number). I'm just confused what the bus drivers are supposed to do, once the leading bus hits a traffic jam or something of the sort. Will they pull over to the side of the road and not move until the leading bus(ses) go?
As @bluGill@kbin.social said, if the busses are super frequent (I would say 5 min and less in between each bus) then nobody really checks the timetable anyway (according to my experience with Munich's public transit system)