I know that "AI" is just a buzzword that is used on the forums to describe a feature. But the operation, or lack thereof, of AI is not really an artificial intelligence problem. It is rather a topology challenge. Now Trainz allows users to create layouts with hundreds of baseboards, and thousands of trackmarks and junctions, most of which are not even loaded at any given time. I think the solution, if any, lies beyond incremental coding changes. I suggest it is possibly a product unto itself.