Why such reluctance to change? The old methods are easy and convenient. They work fine, it is argued, for most market conditions. It is only in the infrequent moments of high turbulence that the theory founders—and at such moments, who can guard against a hostile takeover, a bankruptcy or other financial act of God? Such reasoning, of course, is little comfort to those wiped out on one of those “improbable,” violent trading days.
