In theory something that consistently loses money will make money if the system is flipped over. In reality it doesn't work because often the loses come from commissions and slippage. Other times there's an inherent problem in the design that I guess I have to call slippage although not the type that comes from placing the order. Anyway that type of slippage, lets rename it the "give up" remains the same even when the systems inverted so it will always be a loser but 1 thing most all system testers do is try fading their losing systems.
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