(Bloomberg Markets) -- Nigol Koulajian, founder of New York-based Quest Partners, has beaten rival hedge fund managers over two decades by refusing to follow them into crowded trades. Since the financial crisis, commodity-trading advisers (CTAs), which specialize in trading futures or options, have piled into long-term bullish bets, riding the market up in search of steady gains. That’s left them vulnerable to big losses when volatility strikes—the very moments when Koulajian’s $1.35 billion quant firm cleans up.