The prospect of the U.S. Federal Reserve bringing its $85 billion-a-month bond-buying program to a complete halt over the next few months is likely to have major implications for markets, warned hedge fund manager Stanley Druckenmiller. "I really don't care whether we go to $70 billion or $65 billion in September. But if you tell me quantitative easing is going to be removed over nine or 12 months, that is a big deal. ... The market will go down."