As an Alex, I was most enthusiastically floored by this conversation between two Alexes. Or is that Alexii? Either way, their conversation was spurred by this excerpt from Steve Souders' "Even Faster Websites." Essentially, the gist of these sites is that CSS items are evaluated as a giant list, every time you put in a sub-div element. It's quite a realization, if you''re building sites with 1000's of CSS elements, like Facebook. Potentially, every <p> tag could be causing your viewers' browsers to check every one of those 1000's of elements. And it clutters up your DOM! Yikes! Go read up, because you may be dealing with CSS improperly. Or at least, from improper assumptions.