John Foley,
I think some have a different idea or concept of how a double plateau is configured, including myself.
I think of a double plateau in the context of # 11 at NGLA or # 16 at Essex County East.
Some of the pictures seemed to be Biarritz greens, not double plateau greens, and I think there's a distinction in form.
My view is, just because a green has several tiers, doesn't mean it's a double plateau, given that my context is in the form of CBM, SR and CB's work.
With respect to how they've held up, I think they've held up exceedingly well. First, by still being here, and secondly because they provide such a unique challenge on the approach, recovery and putting.
If I had to identify one factor responsible for their demise in modern design, I'd say it was USGA green spec construction.
They'd be difficult if not impossible to get right, especially a green like # 16 at Essex County East.
Perhaps George Bahto can comment on that.