I see a lot of boundry markers at the edges of Dumont that I frequent; the markers are those tall plastic sticks that clearly tell you to turn around. If there were more of these markers would everyone be satisfied? Perhaps we need to design a marker that is more noticeable?
I'd say that so long as the fence doesn't effect the wilderness (animal movement or what have you) then toss it up! There is no way to get everyone to agree to not go past any boundry. Like ntrsandman said, people already take over the finger dune, ride through camps, and leave their trash everywhere.
Vicki, I applaud your patience and diplomacy. See you @ SSSS!!