Waiting times at stops with multiple departures from the same convoy

[freddyhayward]

   
• This affects networks in small towns where only maintaining one bus is warranted, which services multiple routes through a common "trunk". In reality, these are marketed as separate routes, but in Simutrans-extended, they are only possible through combining these routes into a single line. However, the combined frequency in this trunk is not recognised as such, with "trunk" stops reporting the same waiting times as "branch" stops.
• In the provided example save (see screenshots attached), the two networks roughly equal in size and service, except that Hornidgewood is serviced by a single bus that completes the combined route every ~hour, leaving the station every ~15 minutes, while Lemingcaster is serviced by four separate buses that each depart every ~hour at ~15-minute intervals. Thus the "trunk" stops in Hornidgewood reports a ~30-minute waiting time and low patronage, while the equivalent "trunk" stops in Lemingcaster report a ~8 minute waiting time and significantly higher patronage.
• Ideally,  these two services should be identical in performance, making local bus service more cost effective.
• Savegame: https://drive.google.com/file/d/1tYLAXxCJuPccdLRN3GN0_Q7IaxFpBP-s/view?usp=sharing
• I have also attached a real-world example of such an arrangement from Kyneton, Victoria.