Artists find solutions. Jason England and I had this same discussion and he agreed, any random person can wonder, "Wouldn't it be cool if...?" Artists and creators are problem solvers, they find solutions to "what ifs" - they don't sit around the internet typing up ideas and concepts, and they certainly don't ask for credit over an outdated forum post.
I can't do a pentagon from the back of my hand (and many other ideas which I can write about) but if someone invents it five years from now, I will not beg for credit nor call said person a thief while frantically emailing everyone this exact forum post as "proof". Bottom line is, artists create and release material instead of cause commotion for a sliver of publicity. To quote The Social Network, "If you guys were the inventors of Facebook, you would have invented Facebook."
Lastly, it's kind of difficult to steal from someone I've never met nor had any contact with for over 7 years now (with the exception of one skype session trying to mend things over).
This is silly and hopefully we have better things to do with our time then judge people's products based on rumor of their personal lives and relationships. With that said, XB and Genesis are both a great resource to help you get started in Cardistry.