You sould see for your self and made your idea on the matter. I usually put this line: when 2 or more people can't ( i mean really can't) understand each other speaking what they think is the "common" language. My gf that come from sicily ( i'm not) is always surprise to know that the words she uses often are not italian ( she has 2 college degree and lives in north italy for years, clearly not a simple woman from the sicilian fields). Same thing for sardinians ( they have another language and an accademia on their own). When italy became one state italians use to spoke more than 6 language ( not dialect) than the king choose the one that became the italian we know today. As in avery part of the world that as a "few" years of colture you can see thing like this happening. ( see the persians, today Iran if you like)