Yes, it is ironic that Worf wound up killing Gowron, considering that he was the one who played a crucial role in helping him become chancellor 8 or so years earlier. For a true klingon, an Worf is undoubtedly a true klingon, despite his human upbringing, the empire always comes first. This is truly one of the best moments in the whole trek history, in my opinion anyway. Hopefully you'll get a chance to catch it soon.