I recall getting an email alert when the Nears closure occurred, both from the GCC, and also from the Mohonk Preserve itself. That email includecd a link to this page(of course, there a re more recent alerts atop that one, which is dated 4/13/09, and viewable about halfway down page.http://www.mohonkpreserve.org/index.php?news
It might have been "easy" to post a ranger at the start of Nears, but would it have been a reasonably effective use of donors funds to use a paid ranger in such a way?
Now, perhaps it *might* have occurred to the Volunteer Coordinator to ask for people to do that service... but I am not sure expecting someone to get that idea at that time would be reasonable.
However, now that I have thought of it, Kent, perhaps it is something the supporters of MPNA might want to consider doing. If they aren't preserve members, I think they could reasonably stand on the side near road without worry of accessing the land without membership/day pass.
They could simply say something like "Hi there! Just wanted to let you know there is a small section of the trail/cliff face which is closed to use. It's clearly marked, so easy enough to notice as you come upon it. As a representative of the (MPNA, AG or whatever), we hope you will respect that closure."