[ssnistfajen]

If you can find a link to the article about post-1989 urban deisgn in China, that would be great. I doubt any contemporary urban area anywhere in the world are built (or re-built) in the form of "narrow, labyrinthine alleys unless it's about preserving historical structures. The major roads of Beijing within the 2nd Ring Road were built mostly in the 1950s and 1960s, mostly inspired by Soviet urban planning. Perhaps you were talking about Haussmann's renovation of Paris?

And no, many Southern Chinese cities still have complex layouts in their historical districts (e.g. Suzhou, Nanjing, Yangzhou). Just check them out on Google Maps. No one in their right minds will build anything without following a grid pattern at least loosely in the post-WWII era. Having reasonably wide roads to accommodate traffic is just basic urban planning. Many rapidly growing Chinese cities suffer from chronic traffic congestion because even the roads built in the 90s don't have enough capacity to handle so many cars. Maybe the "eight-lane highways" were needed because of that?

[royjacobs]

The highways were not needed because there are a lot of cars. They are needed because the city is structured poorly and with a lot of segregation between functions so that anyone who wants to do something that is different from the function of the current block (e.g. they want to work but they are now at home, or they want to get a haircut but they're at work) requires a trip by car.

[sgt101]

Funny how natural structures don't tend to grids. A grid indicates a uniformity of need, urban systems are diverse. With diverse structural need.

[intertextuality]

They tend not to be grids because a lot of cities were built before the advent of cars, and renovating would be basically impossible.

Cities that had the opportunity to rebuild (like Chicago after the 1871 fire) make use of grids.

[greatpatton]

Grid structure is not dictated by cars. Roman cities were based on a grid structure.

[njarboe]

Lots of cars around in 1871. I think grids are useful layouts for cities that don't have any motorists. Most of these gridded cities were designed before cars. Modern suburbia loves the cul-de-sac.

[sgt101]

I was thinking of natural structures like the branches of trees and the tributaries of rivers. Because cities rebuilt like that in the 20th c does not mean that it was a good idea or successful.

[njarboe]

A gridded street system is also quite useful for inhabitants/businesses that want to go to an address without a map (or even with one). You can easliy go to a place you have never been to before. This is probably a highly undervalued property of grid layouts for cities before the invention of telephones, GPS, etc.