Peter Z,
No question about it, containment mounding has been used to seperate holes.
When used to buffer the course from the outside world, it's application is useful.
It's cheap to plant a tree, it's very expensive to create seperation mounds, and I don't know of ONE EXISTING golf club that introduced substantive seperation mounding to their golf course after it opened.
As an acoustical or visual barrier at the perimeter, containment mounds serve a valuable purpose, as do trees, but, an infinitesimal number of golf courses added containment mounds to seperate holes, while an enormous number of clubs added them to seperate and frame holes and featues.