One step at a time
The Well-Formed Web will arrive in small steps with each step providing an immediate benefit to either the implementer or the consumer. Check out the Mozquito XForms weblog:
This page is the blog, we style our RSS XML directly with CSS. Both modern standard browsers and news aggregators can process this blog. There aren't different HTML versions and RSS versions, adding a lot of complexity to the back-end, just one XML file that uses CSS to display in the browser, ignoring the CSS when processed by a news aggregator like Radio Userland or AmphetaDesk. [Mozquito XForms]
This technique provides definite benefits for the producer as they don't need to mainain seperate files for the browser and the news aggregator. The benefit for the consumer is that they don't have to go hunting for the RSS feed. Hat tip to Mike Gunderloy.