The Power of Positive Thinking Isn't Just Folklore

It's cold, hard, scientific fact. Or its the absence of it being untrue.  From The Atlantic.

Some thoughts about this from a layman's perspective:

1. The Scientific Method is cool.

2. How about an experiment in which people's optimism is measured, over time, at fixed points (pre-flop, and after the flop and turn) in a game of Texas Hold'em (after being told the % of the time they can expect to win by chance, they are asked to rate whether they believe this time their chances of winning to be higher, equal to, or less than the % they'd been instructed), across the following scenarios: they do this on the computer that plays fairly, or that will cheat either for or against them? Are they more optimistic after winning more than their fair share?  More pessimistic if less? Would it affect optimism levels if they're told they're winning more or less than their fair share, when those statements are true as well as when they're false? When told that the computer will cheat, and when directed that the computer is using a random shuffler? They rate their chances with a magician who is stacking the deck unbeknownst to them, both positively and negatively, they do this with an ordinary human shuffler, they do this having shuffled themselves. (Tangential prediction: gambling addicts would start off at median level of optimism, and would experience much greater swings from positive to negative depending on short-term results.) What about if the experimenter (or the computer) offers encouragement after losses and excitement after wins? What about if the experimenter offers the encouragement only after the result matches the guess and not the probability, or vice versa?

Has research like this been done? I imagine it has; if you happen to read this and you know of it please point me in its direction. Thanks.