Theoretically, it should be possible to make money even with a strategy that is not profitable. I don't mean selling it to newbies for $10000, but by using it in a compound system. Suppose you have two uncorrelated strategies A and B, with A returning 80% profit and B 40% profit. A compound system of both strategies will not return 60%, but likely more than 100% - the whole is greater than the sum of its parts. I think this is commonly known. But surprisingly, this should even work when strategy B is slightly losing, f.i. -10%. As long as it has some negative correlation to the other strategies, adding it to a compound system can theoretically improve the overall return by reducing drawdown. Has someone already made experiences with compound systems from uncorrelated or negatively correlated strategies and assets? What's the best money management for such systems - covariance based or optimal f?