A better way to solve the problem I´ve found is this:
(See picture for example)
The best thing is to have a depot near a station (doesn´t matter how big). Now, as you look at the picture, when the depot near this station is the only depot on the route, a train will most likely want to enter it before loading/unloading at the station. With this construction, this is not a problem because the train can use the two (can be one, I used 2 because of a lot of traffic) tracks leading back to the entrance of the station to go and load/unload his stuff. This way a minimum of time is lost on servicing, and you don´t have force trains to enter the depot everytime they pass it.
The key is to not have depots along the tracks themselves, because that will mess up trains. They will start thinking that they want to enter a particular depot when they pass it, even if they can´t reach it. When you place the depots only at the stations everything should work fine. Oh, one more thing, since the trains don´t enter depots obligatory, they could break down sometimes. However, as Matt mentioned, we die-hard TT pro´s don´t mind building a train network capable of handling such occasional brakedowns, right? I even sometimes stop a train intentionally at a crucial point or bottle neck just to see how the rest will react to it. It´s a good way to test if your network can handle a lot of traffic without jamming. That´s the fun about TT I think.
If you want to view the savegame of the system I took the screenshot from, go to the post about Complex Railroads.
I hope I made myself clear, if not just ask.
Adam
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