Anyone who's run afoul of Facebook's, um, fluid rules for user behaviour can tell you it's like a Kafka novel. (Remember the one where nobody would friend the giant cockroach? Shudder.)
Here's one of the latest lucky contestants: Social Media Today, a Web venture with an active presence on Facebook, was posting URLs twice a day, until one day they discovered they'd run afoul of the site's rules and had their ability to post links blocked.
So how often is too often? Facebook won't say. How infrequently would they have to post to stay safe? Facebook won't say.
Look, I get that Facebook's a private company and if I don't like it I can just move somewhere else - although when you're dealing with a platform that has 400 million users, half of whom log on in any given day, that's a little like saying you can always go find yourself another human civilization.
But there's something wrong if we're expected to treat Facebook like Dinsdale Piranha - forgiving them for nailing our heads to the floor because we'd transgressed the unwritten law. (Which law? "Er... Well he never told me that. But he gave me his word that it was the case, and that's good enough for me with old Dinsy.")