Google has too many rules and grey areas for me to keep up with. I saw an interview with cutts saying you can link your relevant sites to each other and this is fine. Well where is the line between this and a PBN? I have a thin site in the fitness niche, (lol originally I made it just to rank another site before I knew about PR and SEO). Can I link this "relevant site" to my money site and not be sent to the dungeons? While it wont pass anything its still a super relevant link with a good anchor text.