I always assume that if any system worked even half as well as advertised, it would not be sold in the first place. And if they were not confident enough to put money on it, and would rather have steady income from sales, why would you want to buy it? From what I've heard, that's pretty much the truth of it. But are there any others reasons people sell systems, systems which do work? Just out of the goodness of their heart perhaps? Fame and inflating ones ego? System design is more enjoyable than trading to them? Able to trade systems, but unable to control emotions while trading it?
Just curious
Ben