I have a question about Italian, more specific: the formal way of addressing someone.
I have learned in two courses and read in several books that the polite form of addressing a person is to use the third person instead of the second one (although my teacher assured me that in the plural, it's perfectly acceptable to keep the second person, and that the use of the third there is a bit old-fashioned).
So, simply put, instead of "tu sei" I would say "Lei è".
So, I was a bit confused when, on multiple occassions, I stumbled over people who spoke Italian using the second person plural as the polite option. They said "Voi siete" instead of "Lei è", so using the concept of substituting the second person singular with the plural which is also used in German (my native language).
I can't claim that the sources were highly academical (Italian dubs of movies and video games), so I'm not 100% sure on their validity, but because it happened on several unrelated occassions, I'm a bit curious and unsure.
Is this an accepted but unusual form? Old-fashioned? Specific to one region? Outdated? Works only for a certain group of people being addressed?
Thanks for your help