Praising VAR because it would have prevented the Orange County and P&G debacles is a stretch. Many VAR defenders made a similar mistake. These events arose from issues of extreme leverage-and leverage is a deterministic, not a probabilistic, measurement. If my leverage is 10 to one, a 10 percent move can bankrupt me. A Wall Street clerk would have picked up these excesses using an abacus. VAR defenders make it look like the only solution, but there are simpler and more reliable ones. Thanks to Ockham's razor, scientific methodology does not allow the acceptance of a solution on casual corroboration without first ascertaining whether more elementary ones are available (like one you can keep on a napkin).