That pretty much means that by calling someone a "godfather" I can prosecute them for things that normally wouldn't be a crime. What if I call someone a "terrorist," or a government a "regime"?
That's because the threat isn't just the words; it's also a question of intent - and in the absence of time-travelling MRI machines to objectively observe people's thoughts in the past, inferring the intent from context we can observe.
Of course, you could argue that having laws that depend on people's only-indirectly-observable mental state is a bad idea - that announcing your intention to blow up an airport should either always be legal, or never be legal. If you're interested in such questions, you might enjoy reading about the Twitter Joke Trial [1] over one such incident.
I think the point is well made - the jury has to decide what "I can't help you" means, and it means different things depending on who says it. This is the nature of human communication and we can't escape from it.
"This guy murdered three other people!" is no proof that he murdered this particular person.
Because of those rules, calling someone a "godfather" in court doesn't so much get you a prosecution as it gets you an objection and mistrial.
So I used a lazy example to illustrate the point.
But this brings up another key point -- most of criminal procedure can be summed up by "you can't use irrelevant statements to prejudice the hell out of the jury."
All in all a pretty good rule.
Apparently you can push a lot of people into believing a prosecution is not purely political.