Yes, it's all well and good "being in the right" and "having evidence to back it up", but the question you have to ask yourself is "do I have a spare xx thousand dollars to argue the matter in court?"
Inevitably, the aggrieved person is
usually a publicly known figure (read: cashed up) and most likely has a little more cash than you lying around. They almost always have pretty sharp litigation lawyers on hand to deal with such matters.
The difficulty (or otherwise) of proving defamation is not relevant. The potential cost of venting your spleen in the public domain IS.
