Trains treating blocked rails as not existing.

[CreeperDaReeper]

An idea that is both simple and complex.

Also, how often do trains calculate their path? Or do they only do that when leaving a station?

[ratchetfreak]

An idea that is both simple and complex.

Also, how often do trains calculate their path? Or do they only do that when leaving a station?

On a long train line used by multiple trains there will often be a train running along, you don't want a train to "no-path" while there is another one running along merrily.

A train should repath more often, however I think a better way to achieve a more natural distribution is to keep an occupancy rating per block.

This means that the more a block is taken/the entrance signal is red the more expensive it will be to path over it.