[quote=edna_mode]I’m curious — why does the DJIA still hold so much sway as a valid metric anymore? It’s 30 stocks; how is such a small sample representative of a country/sector/economic/company/policy/regulatory environment in such a way that you can make decent predictions about anything?[/quote]

Inertia, basically. There’s a great Planet Money podcast covering all its shortfalls: http://www.npr.org/blogs/money/2013/03/12/174139347/episode-443-dont-believe-the-hype