Despite my efforts on this humble blog, I still think many people don't quite get that, as Yglesias says, walkable urbanism is illegal to build in most places, often including existing walkable urban areas (meaning, new development faces restrictions that make it impossible to build new or redo existing areas in walkable fashion).
But the point of the post is to respond to a commenter over there who brings up Houston. Houston doesn't have zoning, though deed restrictions set up a kind of de facto zoning to some extent, but it still has land use regulations and building codes. Zoning and land use generally get jumbled up, but zoning is more about what kind of function you can have on a property, while land use restrictions are about what kind of building you can build, whether there are setback and parking requirements, etc. So building walkable urbanism in Houston is as difficult (illegal) as anywhere.
