Apart from the fact that the promoters control when and what is happening with the portfolio there is the overriding question of comparing apples (listed equity indices, based on actual real-time transactions) and oranges (prices determined in an opaque fashion, high leverage key to investment rationale).
So triumphant messages such as this one can only be considered public relations unless the data is made public (not just sold to subscribers) and the methods properly disclosed. After all, the real end investor has a right to be fully informed about what his fiduciaries are up to with his hard-earned savings!
http://www.cityam.com/269664/private-equity-investors-nab-their-highest-quarterly
FTAV’s further reading
46 minutes ago