I was just thinking about the following.. What if a newb opened a trading account and his broker decided to conduct an experiment without his knowledge. Every order he made was actually changed by the software to do the exact opposite WITHOUT his knowledge. The market order buy button actually sold and the market order sell button actually bought. If he had a limit order to buy at the bid, the order would actually be a sell at the offer.. it would get tricky with some of the realistic fills but you get the idea. If he was down 500 on the day, in reality he would be up 500 on the day without his knowledge. Also, to keep it simple lets assume he only traded the ES and of course he was charged the same commish.. Would he be profitable after a year?