I understand that both на самом деле and вообще-то are used to correct a misconception or present a clarification of the reality of a situation. However are they completely interchangeable, or (as a native Russian informed me) can вообще-то express some frustration or even anger on the part of the speaker?
For example, if someone offers you a cigarette in a social setting, it's quite polite to say "Actually, I don't smoke." (with a smile, of course). However, my friend told me that saying "Вообще-то я не курю." would sound defensive and reactionary in Russian. He cited the following exchange:
Слушай, у тебя такой кашель.... и ты бледный какой-то... Может тебе пора бросить курить?
— Ага, спасибо тебе! Вообще-то я не курю.