The fact that Azeris are mixed Turkic speaking people that sprung from the Turkish invasion points to the fact that they did not just appear.  They were and are in the location that was Arran that consistent of Albanians, and Iranian tribes.  Furthermore, the fact that the entire area was called Arran, then for some reason was renamed Azerbaijan is another indication that Azeris were not a Turkic speaking group that just living side by side in the Caucus next to the Sakas.  No one said Azeris in the north do not have differences when compared to other Iranians, in fact Iranians are a multi-ethnic, multi lingual group, much like the Kurds in the west have a different language/customs, as do Balochies in the south.  What happened to Iranians in Arran intermittingly, in which the Turks invaded their tribes, and the Albanians were driven out, and imposed their language on them via Elite Dominance, does not change their original ancestry.  You have again failed to give a single rationale as to where the Azeris came from, why they even appear/are part of Iran, even today, and why these ethnic groups even have a Persian culture?  In all, you can concentrate on their differences, but fail to explain where did Azeris come from?  It is astonishing how some choose to skip many important facts, and write pages of texts about Germanic peoples in an article about Iranian peoples.   I think I’ll stop at that.