Zeev, are you saying that if QQQQ goes down that will affect all the stocks in the index? Does it mean that if market goes down the index funds would have to sell all the stocks in that index regardless of the fact that some stocks are worth keeping? So if the nassacre happens, is the downside bigger for the stock included into QQQQ?
Also, what do you think about short term effect on the stocks included into QQQQ? I looked up the charts for last year and it looks like it is usually 'sell the news' right after the rebalancing announcement. But many stocks rose some 10% within a month after the change took effect.