Quote from Thunderdog:
Sorry, but that is arithmetically incorrect. A 2-to-1 win/loss ratio will not make money if you are correct only 33% of the time. If this is not obvious, consider a simple example. You lose $1 on each of the first 2 trades and make $2 on the third trade. This is the scenario under which you propose to make money. However, you did not even break even after accounting for slippage and commission.
Actually, it's a little worse than this unless he'd be increasing the size of his bet after the two losses.
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