Ok, but the traffic light page does not render at all if the tmp directory is not writable. Because of other changes made to Caching and Logging exceptions are raised and the 'welcome' page is pretty fugly.

![screen shot 2013-09-07 at 2 58 29 pm](https://f.cloud.github.com/assets/24086/1101963/8c42a61c-17ef-11e3-8547-31db492452a5.png)

I agree that world writable is not a secure default, but in lieu of knowing the correct permissions it works.