^
Haha you are very correct in pointing out that the mathematical expectation cannot be changed by Fenshui.
In my opinion, the most correct solution that will benefit the gambler is the study of game theory, mathematical expectation and probability theory. This will really help you to understand what are the chances of winning in this or that game.
Feng suit and all other beliefs that people thinks it brought luck when they're gambling is only made to make you feel better when gambling. Being not in the mood while gambling might end up with bad decisions that'll probably going to make you broke. Though it doesn't really have any effects, but then again it is there just to make you feel better.
Nevertheless, calculating your winning rate and risk may help you avoid huge losses and uncontrolled betting.
Being optimistic to win is normal, but knowing your chance and the risk is realistic in gambling. Well, some people are being superstitious, but that's them, we have to respect that and I hope they will still be realistic all the time even if they believe in things to make them lucky.