People who follow all laws and rules frequently do look like idiots. Laws and rules are generally not very self consistent. While banning the exact picture that you posted will obviously not cause any trouble, you have simply taken the covered by body parts to its logical but silly furthest extent. The intent of this rule was probably to prevent images with underage (appearing, since they are not real) models with hands or feet strategically placed to block the bits and pieces. Unfortunately, we must respect the letter of the rule, not the intent, to be in compliance with it. While most poses with body parts blocking a child's bits and pieces would not be considered child porn, some foaming at the mouth radical with an agenda could probably find images that could be interpreted as child porn in court. I don't really like this situation myself, but the penalties for child pornography are so life destroying that you can't really blame the operators for erring on the side of caution. If a bad image is posted and prosecuted before it is pulled, the operators could point to the policy as a means of (some small) defense in a courtroom.