Investing money disproportionately also have a self-fulfilling prophecy effect. It gives your player such a disproportionate advantage over the others, that others probably won't be able to compete, therefore improving your odds of success.
Just fyi though: I have worked in markets for about ten years...I have seen this over and over. I studied economic history...I have read about this over and over. And the subject almost never makes it out alive. Usually, this is psychological. Most people get involved with clear heads but that clarity doesn't survive the rush of the bull market/greed...they want more, they start to believe their own bullshit, they end up fully invested at the top...they get carried out of the market.