Well, there are a lot of people who've written a lot better stuff on poker odds: Sklansky, for example (and if you want to google "nofoldem" you might find something).
That being said, I'm pretty sure that this does produce accurate results for the scenarios I mentioned: what are the odds of hitting a four-flush from the flop to the river? I think roughly 31.5%
As to how to use that information, therein lies the art of poker. I just wanted something that I could take a quick look at if I wanted to know my chances of hitting a certain card.