So, these days this style of thing is not uncommon. For example, much of the Rails community uses Sass, a language which compiles to CSS. In development mode, it gets compiled anew on every page load. This doesn't happen in production: there are a few ways to make it happen, but basically, in production it looks like auto generated CSS sitting on the hard drive waiting to be served up quickly.

Doing the same thing with WebPutty would take maybe a dozen lines of code. I'm assuming anyone with multiple environments can make it happen in their language/framework of choice.