Nothing new here. Basically women tend to send mixed signals and men tend to misinterpret those signals. Oh, and if you want to increase your success rate then having a shared interest with whoever you're trying to flirt with is a good idea.
The title should have been "A report on.." rather than "A guide to.."
Am curious to know if this game would have the observer effect. I would guess that a lot to flirting lies in the fact that such "signals" are natural. If someone manages to study them and lay it out as steps, and many end up following it, wouldn't there be a shift in the trend?
i.e., If I know how you play the game to your advantage, I will adopt a different strategy.
It's not a scientific study, it's a summary of a lot of studies, but you will probably not gain anything. Nearly everything it says is completely obvious. It doesn't say how to flirt effectively. It explains when flirting is acceptable.