Multi-strategy hedge funds - are they limiting?

The multi-strat hedge strategy have seen a surge in new funds over the last year and has been the focus of investors who want hedge fund diversification. A multi-strategy hedge fund has a broad mandate to find the best opportunities across all hedge fund strategies. Prequin, the alternative investment data collector, through market survey work, has looked closely at the portfolios of multi-strategy hedge funds. Their work presents the most popular strategies used by these managers. The majority focus of these funds seems to be directed to the most popular hedge fund strategies. The Prequin survey shows that 2/3 of multi-strategy managers will use long/short equity. This will outstrip the next two strategies, event driven and long/short credit by a factor greater than 2. The multi-strat manager will have a strong focus on equity market alpha and beta relative to other factors, albeit the beta may be much lower than the market.

I find this odd survey result odd. It would seem that a true diversified multiple strategy manager should have some combination of all different strategies. Given the diverse collection of strategies and correlations, it would seem that the low number for some strategies would mean that multi-strat managers are under-diversified. There will be more diversification with a multi-strat hedge fund than what would be received from a single manager, but not having exposure to all strategies seems to limit the usefulness of a broad mandate.