[ascagnel_]

Also, there's no off-the-shelf version you can buy (this is all new technology), and it has to integrate with other railroads. For example, in the NY Metro area alone, you'd have to integrate the Long Island Railroad, MetroNorth, Conrail, Amtrak, New Jersey Transit, and possibly other industrial rail lines I'm not aware of. That alone will take a while to get right.