Building for the Short Now
I just spent a couple hours trying to retrofit a site built three years ago with some spiffy new accessible CSS. Not so easy. Once upon a time when you built a site using CSS you had to beware of Netscape 4’s absent mindedness. Of course, if you specify in your style sheet that the body of your HTML should use a particular font it should apply to every element contained therein. However, poor old Netscape 4, by the time it got down to a linked item in an unordered list contained in some div or another would look like it just walked into a room and couldn’t remember what it was after. Poor dear — had to continually remind it by building all sorts of redundancy into your CSS and, as I’ve just discovered/remembered, your HTML. Tsk. Having a class applied twice to an element when you’re using relative font sizes is not a pretty thing.
All valuable reminders to separate content from presentation and keep the HVAC system separate from the foundation or whatever example it was that Stewart Brand gave. Obviously you should never have me build your house, your web site, yes, your house no.