I disagree here. I strongly think that there is absolutly no difference between "that was a good movie" and "that was a good f-in movie." Except that the latter just makes you sound crude. Instead of thinking of cuss words to put in your speech for emphasis, why not try to speak more intelligently? Why not dig through the English language for more descriptive words that are clean to modify what you're saying?
That's just my thoughts.
Please explain why you juxtapose using swear words and "speaking intelligently," as if these were somehow mutually-exclusive, because this claim has not been substantiated.
I think one should use the words that most precisely reflect one's meaning in the minds of one's audience. Sometimes, the words that most precisely reflect one's meaning for one's listener will be swear words. There is no reason to conclude that this is a bad thing, unless one starts with the presupposition that swear words are inherently "crude" or "stupid" or "bad."
All words are completely artificial constructs, strings of phonemes to which we, collectively as a culture, have assigned semantic meaning. There is nothing inherently good or bad about any particular series of phonemes. It is only the meaning we assign to that collection of noises that has value, whether positive, negative, or neutral. I think it's far worse to call someone "stupid" (which is not a swear-word by any reasonable definition) than it is to use the f-word as an intensifier when describing how awesome you thought a movie was.
Besides which, as Stan and others have said, cusswords aren't just empty placeholders; they have semantic meaning in the minds of our listeners, and specific convey nuances that other words would not. As another simple example, the phrases, "making love," "having sex," and "f*ing" describe three entirely different acts, though those acts have some elements in common.
I guess in summary, swear words
do have a practical purpose, and there's only something wrong with swear words if you presuppose something wrong with them.