" ... if a traditional singer sings traditional songs but starts to improvise [ in jazz style] what is he then?[apart from being experimental].he becomes a jazz singer, because of the style of presentation."

Again, GSS, please name a traditional singer who improvises in jazz style. Because, I suspect, you can't. Postulating the existence of such a person is a waste of time and gets us nowhere. If, on the other hand, you can point to such a singer then please refer to Howard Jones's well argued post above.

It seems to me that you're either deliberately 'muddying the waters', arguing for the sake of arguing, or over-complicating things for no good reason.