They're playing different strategies. If you're a defense-driven team you play to win primarily be keeping the other team (call them the black swans) from scoring. To bring it out of metaphor, it's about risk-adjusted maximum return.
If you're an offense-driven team you're trying to put more points on the board. The S&P 500 is a decidedly long bet on 100%, large cap, primarily western corporate equities.
>So the "unexpected strength" came from performing "in-line with historical averages"?
Hedge fund guys are usually bears and as such they've successfully predicted 9 of the last 5 recessions. They're perpetually prepared for or waiting for history to be proven wrong. It is within that context that they are seeking a maximum return (and justification for high fees).