If they have to have multiple platforms at each station anyways, it might make sense to essentially have three lines - A<->B, B<->C and A<->C, instead of A<->B<->C - and only run direct. At least in that situation everyone would be getting off at each stop, which could simplify some things - and it naturally splits passengers into two platforms.

That sort of routing is also significantly improved by having smaller, independent vehicles (well, once the number of stops goes up) - sort of like the Personal Rapid Transit setup at WVU. [0]

0: https://en.wikipedia.org/wiki/Morgantown_Personal_Rapid_Tran...