> Cussing does not make you immoral.... It is often a symptom of an already existing lack of or laxness of morals.
I would argue that an intentional lack of cussing denotes considerable immorality. Cussing is about the best way possible to express honest emotions; and hiding ones emotions is a form of dishonesty. Habitual dishonesty is generally accepted as immoral.
I do not trust anyone who is unwilling to express their true feelings.
Cursing doesn't express true feelings since every curse and combination of curses out there is just another cliche. If your true feelings reside in the common language of vulgarity, then those feelings aren't worth expressing. Also, cursing isn't used so much to express true feelings today, it's used as punctuation (exclamation points, primarily) and lacks any real meaning.