A bike I had many years ago had a double clamp-on cable stop at the lower end of the down tube, a clamp-on cable stop on the chainstay just past the BB, and a single clamp-on cable stop on the seat tube just above the BB. Short sections of housing ran between the stops. It was quite effective, and somewhat flexible.
Unfortunately, none of the cable stops were Campy, so they are excluded from this build. 🙁
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