Lane A is occupied by train.
Lane B has signal red (by circuit control)
Lane C is empty and green.
But train doesn`t know about Lane C. It goes to B and stuck in red signal.
If we place a wagon on lane B, train goes as intended (to Lane C).
So train ignores (in some cases) circuit-controlled signals
![Sad :(](./images/smilies/icon_e_sad.gif)