DislikedMost people say that when backtesting gives them an answer they don't want to hear.Ignored
You need to know how backtesting works, if particular backtesting method is suited for the strategy that you try to backtest. You need to know how to do it right. And you need to know how to interpret and verify the results.
Backtesting is a powerfull tool if you know how to use it... it can give verry acurate results if done correctly.
In this particular case (because of the simplicity of the strategy), i would say, that Phils backtest results are completly valid.
I'm not insane; my mother had me tested.