> In my initial CSS implementation in 1995 I used the “SkyBlue” constraint solver to resolve conflicting style sheet statements. (By the way, “SkyBlue” and “Cassowary” were both developed at the University of Washington.) Having a constraint solver allows you to express relationships between arbitrary elements and have conflicts resolved automagically. However, things can get complex when elements disappear and new ones arrive, like they do through DOM operations. Circular dependencies must also be handled gracefully. Therefore, the idea of allowing CSS to express layout constraints between any elements were dropped at an early stage.

That was the biggest mistake, IMO. John Nagle's comments here [1] express that point really well:

> With Dreamweaver 3 and tables, it wasn’t necessary to look at HTML to lay out a page. With Dreamweaver 8 and CSS, the page designer must understand CSS, HTML, and probably Javascript. That’s was a big step backwards. The CSS system is just too programmer-oriented. And I’m a programmer. (Programmer as in MSCS from Stanford, the Nagle algorithm in TCP, inventor of ragdoll technology, real-time robot vehicle control, not programmer as in “writes some Perl”. And my first web site went up in 1995.) It’s not that CSS is hard; it’s that CSS is bad.

> The worst problem with DIV-based layout is that the layout system is too weak. There’s no form of “grid” layout. There’s no way to relate a DIV to anything but its predecessor, its parent, or an absolute position. The system is just too dumb. That’s why people have to stand on their head just to get three columns to work. Tables actually are a better designed layout system. Table layouts allow table cells which span multiple rows and columns. If all tables could do were simple grids of cells, the CSS approach might make sense, but tables are more general than that.

[1] http://www.raizlabs.com/graiz/2006/09/25/ten-reasons-why-css...