I don't think being in the Russell opens IDEX to a significant amount of discretionary buying. The index funds HAVE TO BUY IDEX in proportion to the percent of the cumulative Russell market cap it makes up. Most non-index small cap funds could already buy IDEX if they chose to.
If I could afford to buy all of them, I would not need to buy any of them and I sure wouldn't be spending time on the message boards!