Is this the next "planning" fad?

In recent years the idea of zoning which segregates commercial districts from residential neighborhoods has been changing to the concept of "walkable communities" where just the opposite is true. Professional planners probably have the same arrogance and liberal politics that most journalists have, because the very nature of their profession presumes that experts know what's good for you and me than we do.

Today, there's a that the new trend is toward smaller homes, "cottages", in clustered communities. I've been working on zoning for the past 10 years, starting with the assumption that planning is a good thing. As I've noticed these fads that seem to be influenced by environmentalism as much as the aspirations of the middle class, I've started wondering about that assumption.