Setup time - about 15 to 30 minutes. This is based loosely on the runs from Hoboken to Northern New Jersey, and takes somewhat from the Long Island railroad's Southern and Northern spurs. It begins as a two-line operation that can handle two to four trains easily. The foundation is the previous commuter line with an additional line. Both lines run spur service to D. For added interest, a connecting link with one or two pairs of switches can be added at point X to connect the Black line with the Green.
Green line can handle two trains easily.
You can add B to C service with two switches. Of course, the original two-train operation on the Black Line makes this busy. The additional work caused by the MOW train can require switching Black line trains to detour along the Green line, and vice versa. This layout can be set up in about half an hour. Here's where we expand on both the aforementioned layouts.