Allow trains to reverse on any birectional track instead of only dead ends

I'd simply love for train pathfinding to consider any branching path "behind" the path of travel instead of only considering this when meeting a dead end. As long as the train has enough space to fit within a bidirectional track segment the branch behind it should be explored in pathfinding.
As a bonus this would prevent trains from running all the way to a dead end to reverse when they could do this sooner.