Once golden, Robert Rubin's hedge fund proteges lose some luster

BOSTON/NEW YORK, March 27 (Reuters) - Learning to invest on Goldman Sachs' risk arbitrage desk, made famous by leader Robert Rubin, was once seen as a fast track to fortune. But the band of hedge fund protégés who mastered their trade under the former Wall Street star and U.S. Treasury Secretary have stumbled in recent years.