Where is the evidence presented that supports any of these claims? I realize most of the seem like common sense but as far as I know many are in fact false. In

Where is the evidence presented that supports any of these claims? I realize most of the seem like common sense but as far as I know many are in fact false. In particular, the argument about semantic markup seems pretty dubious. Currently, I'm not aware of any search engine that cares about new HTML5 semantic tags. On that note, is there even even one example of assistive technology that uses semantic markup? As I understand it ARIA tags are needed for this, semantic markup is irrelevant since most (all?) assistive technology is outdated as far as browser technology goes.