No winnig systems?

[Robin Hood]

Hi, I have heard so many times that there's no winning system in roulette.  How do people then explain
this Gonzalo Garcia-Pelayo guy and his family who won a lot of money in many casinos. 

They even published a book, and describe how they did it.

[bombus]

They were targetting bias wheels, not playing a system.

Cheers.

[bombus]

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