Enlarge catchment area(trick)
The different type of station in OTTD has various range. Example, a Truck/bus station has 3 tiles, a train station has 4 and docks has 5. This knowledge can be used to make the station reach further.
Well, will another piece of train station be enough?
No, it is one tile away, but that docks seems interesting, do the dock reach?
And since dock has one more range than a train station have, it does reach. This is a simple example how to use the extra range the different station type have. Another normal one is:
Here the train station is connected to the truck station. Instead of using a truck, there is one tile gain. Which generally matters little, but in some cases, one tile may be have an impact.