But Vanguard's Brennan counters that REITs often are correlated with small-cap stock performance. And precious metals advocates believe that the funds will always be needed as long as there is potential for bear markets, high inflation or weak dollars.
"You can also look at it as insurance. That is what we do," Eveillard says. "We look at gold as the ultimate hedge, just in case we get what Peter Bernstein calls an extreme outcome. That's a fancy way of saying Mr. Greenspan [is] falling flat on his face."