Actually it's not facetious at all. The point comes from his mentor Benjamin Graham, which relates to the difficulty in recouping investment capital following a loss (ie: making your money back after you break the rule).
eg: You have $100k in your investment account. You have a bad year and lose 50% of your money, leaving you with $50k. You now need to have a 100% return in the next year to just make your money back, even though you only had a 50% loss. Seth Klarman, another highly successful value investor like Buffett is also a proponent of this way of thinking.
eg: You have $100k in your investment account. You have a bad year and lose 50% of your money, leaving you with $50k. You now need to have a 100% return in the next year to just make your money back, even though you only had a 50% loss. Seth Klarman, another highly successful value investor like Buffett is also a proponent of this way of thinking.