Don,
Also, to answer your question, while it is easier to get water to the basins, for drainage, it would be better to have the fw on a small rise where water drained away! Having to take care of drainage somehow is one of the downsides of routing in the valleys, and valley fw's are something I suspect you would NEVER see on a Tommy N designed (or consulted) course!
Having seen the CB site, I can attest most of those valleys were man made, and the visual separation on a tight site, and probably the idea of recreating some of the linksland characteristics of Irish courses were the biggest reasons for building those.
It is possible, BTW, with Sand Hills NO. 2 or my Quarry No. 6, to effectively route an "along" the plateau or ridgetop fw and when I see that rare ridge runner fw, it really stands out to me. It is naturally more penal, so it helps to make them a bit wider than other fws- not only for the fall off, but also because those ridge tops tend to stay windier.......