Whenever I hear about planning efforts that propose a "non-regulatory" way to achieve desirable land use results, and especially when those better results are supposed to derive from "voluntary" efforts associated with "better coordination," one of my favorite Bob Dylan lines always comes to mind: "I just said, 'good luck.'"
In the land use arena, local communities have the ability to "regulate" what individuals do, and can, directly, say what will be "permitted" and what won't. When local communities use such regulatory powers, for instance by drawing urban limit lines, or by prohibiting developments on commercially viable farmlands, they actually have some success in changing behavior. But the track record of "voluntary" programs is not that good.
In case you don't know the quote, or have forgotten the context, I tend to see Dylan's observation in his song, "Bob Dylan's 115th Dream," as a commentary on what amounts to the entirety of American history:
But the funniest thing was
When I was leavin' the bay
I saw three ships a-sailin'
There were all heading my way
I asked the captain what his name was
And how come he didn't drive a truck
He said his name was Columbus
I just said, "Good luck."