They are not a myth.
Can they work and with which broker and account trading balance.
They test well but doesnt mean trading forward it can work since trading forward and testing backward are really two different things.
People are better off making their own strategies that way you learn more about trading as well as about strategies.
Biggest use of strategies is they can be used to provide trading signals to the user who design, properly test and use a good strategy to monitor the market before taking manual trading decisions.
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