I tested the use case I could've really used this for, but it doesn't seem to be able to do this: "Biel to Zürich, but not through Grenchen".

The SBB timetable app and website can become really unhelpful if there has been an "accident involving a person" [0]; other than that, I've got little issues with them day to day.

But it seems your model doesn't have a way to know that the IC from Biel to Olten goes through Grenchen (it only presents the obvious routes that wouldn't work in this case).

[0]: https://company.sbb.ch/en/railway-development/services-rus/r...