The concern with these sorts of strategies is that you might discover the problem quickly. Say for instance if the stock you shorted doubles in value and you lo

The concern with these sorts of strategies is that you might discover the problem quickly. Say for instance if the stock you shorted doubles in value and you lose all your money. Even if there's only a small probability of that happening in a given year, going bankrupt by definition negates all the gains you got previously. Worse still, when you short stocks it is actually possible to lose more than your entire investment so a strategy can work amazingly 99/100 times and still have negative expected value.