I recognise this one. I think my mum actually bought this system AGES ago, (in the mid to late 80s I think), and we followed it for a while. It got a few good results early on, but then hit a bit of a bad patch and as with most people, we basically discarded it then. But having said that, there is a bit of common sense in amongst the rules and as Chrome said, there's no reason why it couldn't perhaps be profitable with the help of a few extra filters.