Surf, for some reason this brought to mind something I read before. I always wondered why an intelligent man never managed to learn, you yourself say he seemed to understand and know, and yet he didn't. Only he will know for sure what was in his mind, but I did think of this passage.
"There are ways for hedge funds to game the Sharpe Ratio by behaving like undercapitalised insurance companies. For example, a fund can sell options that insure against extreme swings in the market. For months and maybe years, the insurer will collect a steady stream of premiums from these options, delivering consistent, market-beating returns; but one day the extreme market swing will occur, at which point the fund will go bankrupt. Theoretically, unscrupulous hedge-fund managers may deliberately take this sort of hidden risk, calculating that the extreme swings may not arrive for years, allowing them to grow rich in the meantime."
Page 397, More Money Than God by Sebastian Mallaby.