As for the unmanned yards, I believe that CTC has the flexibility right now. You just set the favored direction to outbound, and every once-in-a-while request to let a train in can be handled by toggling the exit to inbound - and when the train is through, CTC will turn the exit to outbound for you. In the future, when we have the capability to communicate with the neighbor about how to interchange the trains, some exits may be "unmanned", and the crew have to call you (instead of your neighbor), and some exits may be grouped together (one level higher than the group of exit tracks we have today), so you have to talk to that man responsible - this is a proposal of a fellow CTC user.
Actually, for these yards, I would honestly dump out the arrow and have the crew call every time they want to enter the main track. Or if they need to foul the main multiple times I would just tell them when they need to report clear of main (or if no traffic is around, just tell them to do their thing and then report). After that it would be up to me to keep other trains out of their way, by blocking the signals.
Also, for single track main line exits, I'd dump the arrow and implement a handshake system either by electronic token or telephone. In reality, no one calls "please open an exit", instead it is "Can you accept ###?", and the rest of the conversation is really easy to guess.
Those single track platform blocks are usually set up
a) to let the user visually see what's heading his way
b) to make sure that outgoing passenger trains are treated as a priority after they have passed the last platform on the territory (for sort of "scoring purposes")
c) to maintain correct scheduling of early-running passenger trains that stop at locally controlled stations in the middle of the user's territory
d) allow for some interaction between the opposing trains stopping at out-of-area stations which have only one platform.
Basically these single blocks would only need to prevent an opposing train entering before letting the first one in. TD3 can achieve this, so I'm pretty sure that CTC could be programmed to do that. Since the platform blocks are used by trains which first leave the territory and then nearly immediately re-enter to the platform block (or vice versa), the route ahead of the train could be cleared even before the train leaves the (preceding) block(s) -- for example, if a train standing at the isolated platform has a set departure time of 14:45 and it is set to exit and re-enter after a short delay, the route ahead of the re-entry point should become cleared before the train actually leaves the platform (representing the actions by the "other" dispatcher).
