This theory would likely work for an individual stock, but the QQQ is a tracking stock, deriving it's value from the NDX. The QQQ follows the value of the NDX, not the other way around. Any attempt to artificially depress the price will make it undervalued compared to NDX, thus bringing in the bargain hunters. I just don't see the QQQ straying far from its inherant value.
Additionally, we are not talking very many shares compared to the average daily volume.