Harvard's average real annual return is 10.2%
(Piketty's book "Capital" p569)
You need a team of very talented investors to get these types of returns y/y
[0] https://www.investopedia.com/ask/answers/042415/what-average...
If the S&P 500 falls 10% in a given year, I can hold 100% cash, light 5% of it on fire, and outperform the S&P 500 - that doesn't make it a sound long term strategy.
https://www.bloomberg.com/news/articles/2018-06-26/harvard-b...