Bus is a bit of a conundrum.
It is clear that the designers had one game and one style of playing it in mind during the design phase. In practice, I've never played the game that way. The first clue was the listed playing time of 2 to 4 hours. I've never played a game that lasted much more than 90 minutes. Final confirmation came when I played with Gerard Mulder, a fellow Hollander and designer of Wortelboer and other fine games.