Renaissance doesn't run mutual funds. They aren't taking outside money in the market-beating fund.

Funds like Renaissance's have minimum investments in the millions, are often invite-only, etc. We average investors simply can't play in those leagues.

Past performance is not a guarantee of future returns?

People have been saying that about rentech for the last 20 years. People have also been saying that about berkshire hathaway for the past half century. At some point, past performance IS indicative of future returns.

I'm not sure about any Rentec mutual fund, I don't think such a thing exists, but aren't the funds they have open to institutional investors not doing particularly well?

When most people say Rentec they think Medallion, which while being spectacularly profitable over 20+ years, is now a closed fund only open to current employees last I heard.