I am wondering if there is any reason to keep the bus wire separated when running around the layout? I am not really versed on DCC just yet, but the "digital" part of this leads me to ask the question. Is there a true digital signal moving through the wires? If there is, then it seems to me that unshielded wire would not do well in close proximity to each other due to the possibility of crosstalk in the wires. Or is it OK to just run them through the same pathway all the way around? Thoughts or help?