Pat,
We had such a course in our area that was a nine-holer w/dual greens. Well, let me clarify, there were large surfaces w/dual flagsticks on holes # 1, 4, 5, 6 & 7, but they were sectioned off by huge spines or ridges, effectively transforming them into 'separate' greens. Hole #8 had two smallish individual greens, one about 100 yards short of the other. The remaining greens were rather large and they easily held the two cups. There were quite a few teeing areas, creating various looks, and one hole had two distinctly different fairways.
My favorite was the finisher, a 210 yard(tips) par three built in the Redan fashion that had a totally exposed and treeless skyline green built in the Redan fashion. It could be 7 iron or a driver, or nearly impossible in a crosswind.
Sadly, the owner passed away and his kids sold the land. The only 'players' enjoying the course now are the Black Angus cattle that are ranged there.
Edit: When playing to the 'dual' greens you had to stay away from landing on the 'other' side or you'd face a sure 3-putt, the spines and/or ridges that divided them were that severe.
I think it would be good to see more of this done, especially on nine hole courses.