He's not forgetting it. To simplify: if you want the market return, there's no point in paying a hedge fund manager: just invest in an index fund! And if you're really bullish you can invest in index futures or (say) ACME DoubleMarketReturn fund that returns double the profits or losses of the market.
The point of investing in a particular hedge fund, as well as actively-managed mutual funds, is that you expect its manager to pick good stocks, better than the average, so you get "excess return" (a.k.a alpha). What wtvanhest is saying is that, essentially, it's a closed system and if you sum all their "excess" returns you get zero.
wtvanhest is not quite right (see Crisscross' comment), though it's much more informative than the linked rant.
The point of investing in a particular hedge fund, as well as actively-managed mutual funds, is that you expect its manager to pick good stocks, better than the average, so you get "excess return" (a.k.a alpha). What wtvanhest is saying is that, essentially, it's a closed system and if you sum all their "excess" returns you get zero.
wtvanhest is not quite right (see Crisscross' comment), though it's much more informative than the linked rant.