Yeah, if you believe that you can pick the winners, then the lack of correlation means if you pick all winners you do much better relative to everyone else (and if you happen to pick all losers, the opposite). I don't see the connection to indexing. If the SP500 moves up 8% a year over the next decade, then your SP500 index fund isn't going to care whether (1) all 500 (or 502) stocks all moved 8% each year in unison, or instead (2) you had a wide range in individual components, from -100% to + whatever%, that netted the index 8%. Maybe in the latter your fees would be slightly higher as the index fund managers had to deal with widely changing market caps, but the ride is essentially the same. The only way you would feel left out in the second scenario above is if you kept reading or being inundated with people reporting their great results after picking the winners. But history tells us that information is heavily biased (survivorship, sensationalism, etc.). And that's what the articles above seem to suggest, that indexing will fall out of favor not because of lower returns, but because of the perception that people are missing out. We know they're not, and one of the reasons I keep visiting here, Bogleheads, etc., is to keep reminding myself that, inoculate myself against the temptation.