Well here in jersey we don't pipe house's but i will say i go up and over with my runs regardles. It allows access later to know where things are when your crawliong in the hot attic in the middle of july? My only change on this is in kitchensand baths. other wise its up and down or down and up if there is a basement or crawl. Sorry i cant help on the pipe part but for romex this is how i do it. i also drill out with a larger hole in the begining to allow for additions later.
