It's not always the case, there are other strategies, the system can be cracked, there are weaknesses, when there are so many markets. You just gotta know how to exploit the weaknesses, you need information and know the games inside out.
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Not playing the game teaches you nothing. Learning risk management is a form of intelligence. Understand the games and the risks. odds are set from weight of money odds of occuring. Remember that. I will be putting together a guide soon.