@Andy Chase: What is so "disgusting" about suggesting the possibility of avoiding HTML rendering problems using an alternative technology? Would you care to elaborate? Silverlight is being used in a large number of media and LOB applications, providing user experiences that would be very challenging using HTML/CSS/JavaScript. I'm not saying it would be the right or best solution to Jeff's issues, but sometimes a problem like this reveals more creative opportunities than struggling in the same direction.

It's thinking outside of the box, but... Perhaps all the techniques for shaping the HTML that ends up in the browser could be avoided by reimplementing the SO family of sites as SilverLight apps? Then you'd have a state-of-the-art UI design and rendering experience, all the benefits of XAML and skinning, and no more of all these HTML hacks. Also, the SO servers would have less loading (serving just the data, and not the whole UI and the data), and lower bandwidth. Of course, although SilverLight is pretty pervasive, it's somewhat limited on Apple's mobile devices...