Danny,
In a private message...responding to what I considered (even as a former US Army Warrant Officer Helicopter Pilot and former Police Officer....two professions that require you to have armor plate instead of skin....when it comes to banter!) a rude, ugly, and devoid of any redeeming value post, suggested that there was banter...and there was banter. I assured the individual that his banter lacked the intellectual basis upon which geniune humor is based and that he should reconsider his style, manner, and construction. I would hope that he gave my advice some fair consideration and that his future attempts might be better reading.
Maybe you ought to charge an annual fee of a Tuppence....then you could correctly tell the protesters that there is no "free speech" on pprune and thus cut off these kinds of complaints. But.....then they would scream at the outrageous prices you charge for membership or something!
I might suggest those that think uncontrolled participation is the acme goal of these kinds of internet forums.....then you should shift to JustHelicopters....that way you will not feel constrained to any sort of guidelines. Bon Voyage!