... settled investor complaints of his failure to follow his own rules ...
Simply points out that traders must follow their rules. Every trader knows that.
For publicly traded funds (that which you are referring to), they must also submit to strict reporting requirements regarding prospectus and continuous disclosure. Obviously, they did not.
Every evolving trader also knows that when the rules start to not work as well, then they need to consider and backtest changes to their rules.
I trade.
I have rules.
The rules work and I know exactly how well they have worked.
The rules are backtested on a computer using hoards of historical data on large numbers of stocks and indices over long periods of time.
The numerical results speak for themselves.
When I see that the rules could be changed to improve results, I take notes. I do that all the time over many months before testing any changes to the rules. It can literally take ten to twenty hours to implement and test a single change to the rules.
The whole process is not much different than how humans learn to do anything.
The baby, the quintessential owner of positive attitude, learns how to walk through experimenting; and that inevitably leads to falling and possibly to serious injury. But they can see the swarm of people around them who have succeeded so they demand of themselves the same. They are not held back by those who, due to serious injury of body or lack of soul, are condemned to spend the rest of their lives in a chair or lying down.
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