If you had polished your social skills, wouldn't you expect to have additional discussion options not available to a clueless lout?
No, because 'polishing' social skills only applies to those who are following the same etiquette you are developing. I can see skills like High Class Etiquette, which would help in specific social situations, but which would also be a hindrance if used in the wrong situation such as when talking to street thugs who think you're being snobby to them as a result of it. In that case, street etiquette or streetwise as it is more commonly known would be more applicable but using that on a noble would make you look like a lout.
Nope. All you're talking about there is applying specific situational modifiers. You still should expect to have more options overall when you've enhanced your social skills.