- Use relative font sizes to allow all users to see the text if they are visually impared or for any reason like to have non-standard font sizes.
- Use a fluid-width design but with a reasonable maximum limit to make sure those unenlightened who browse maximized don't hurt their eyes.
- relative font sizes
- a must if you're designing anything that isn't made to be printed. (and no, while a webpage can be printed, that is generally far from it's original intent) there are way too many combinations of resolutions, font usage, rendering methods and physical displays to say "12px aught to be enough for anybody".
- this is not as hard-and-fast as Inferno would like to think it is. There are valid reasons for using a fixed-width layout. However, they generally don't apply when you've got columned text. In that case: yes, elastic width is the clear winner.
- Assume some of your audience does not always have these installed. Make it nice for those that do, sure. But with the popularity of NoScript (a plugin for Firefox to set up JS whitelists), and the ease of browsing the web on crappy displays (phones/PDAs/pagers) you've got to make sure that they can at least get your content without huge hassles.
This means, that this rule should be extended, really. Go ahead and make those nifty-layouts and weird page designs. But make sure that there's something fairly simple for people that don't want to read your content that way. Something very flexible. Either by making sure your main layout is robust enough to work without colour, or with images off, and differing default colours. And, especially for the phone users, make sure that your pages semantically make sense: put your content at the top of the physical HTML, and navigation after, just in case everything isn't getting floated to a column off to the side because the screen's too narrow, or somebody is using a screen-reader. Yes, sometimes people need to browse web in lynx. And it's really not that hard to accommodate them.
The objective of web technology is to enable all people from all over the world using different client applications to see the same content.
And hey, he even follows his own rules, on The Right Glue (but he missed rule 8: stupid names are stupid). It's a simple, but solid layout. And he even made an RSS feed, just for me!