https://www.reuters.com/article/us-retail-trading-funds-gamestop-analysi/analysis-to-the-brink-and-back-on-gamestop-wall-street-vs-reddit-idUSKBN2A00NI >On three hours of sleep a night and with no time to eat, one New York-based hedge fund manager overseeing billions in assets called last week the most stressful of his life.