Hello sam!
It works in practical scenario too. It is mainly used in designing the TDM,OFDM,TWDM…and many more systems.
If you wish to know if it works in optisystem , you need to include delays in your system. These delays do not have any physical significance in optisystem. These are used just for simulation purpose here. When designing a practical system you can remove these delays. For bidirectional fiber to work in optiwave, you must include delays.
please refer to chapter 5 of the tutorial i am attaching below.