My fault for dropping the ball with a reply here. Sorry.
The policy is to not allow links to training/nutrition sites, blogs, or forums. You can certainly link to sites that don’t relate to those topics and can refer to those sites without a link (“I read a bench article by Charlie Chaplin on Livestrong”, “Benni Magnusson’s program on EliteFTS”, “Layne’s cutting plan on bb .com”, whatever along those lines.)
Some long-term users who shall remain nameless have, at times, tried taking advantage of this and started drifting into borderline-spammer/advertising territory when they decided to start a business and/or blog. Bad apples have spoiled the bunch. This is why we can’t have nice things. Insert other appropriate metaphor. Any user can have a link in their profile, so that’s still a way for “passive, acceptable self-promotion.”
There could be other variables involved (thread context, poster’s history, etc.), but generally-speaking, if someone’s edited for linking to a non-training/nutrition/supplement site, it could be an error.