My layout was built before DCS. It is 3 levels, 35x16, and any train can go anywehre on the layout at any time. For conventional, many blocks means better control It has 70+/- blocks, each controlled through a SPST toggle switch on the control panel. The panel is divided into 6 sections, each covering an area of the layout. From the panel a single 14-gauge wire goes to the center rail of the block, preferably near the center, 14 gauge all the way. From the transformers' U posts, there is a loop of 12-gauge wire going completely around the layout. All outside rails and accessory grounds are tied into it.
My son gave me a DCS system the week it came out. No way was I going to rewire that monster. I inserted original issue Rev G TIUs between the transformers and the control panel, and have been happily running DCS ever since (about 18 years). I don't have star wiring, I don't have twisted pair. I did place 18-volt bulbs across the rails at a few sidings; that's another, rather long, story.
Having the toggle switches is still great with DCS. I can cut off a section where there is a derailment until I can get to correct it. I can test equipment without activating other equipment. I can kill trains so they don't start in stealth mode.
The late Marty Fitzhenry, who worked with MTH in developing MTH, also rejected the start wiring idea. He also had common ground. Forget the twisted pair and equal length c--p.
