What? Proto-Indo-Europeans have nothing to do with the Mitanni? I'm sory, but that's crazy.
Read what I said again, the meaning of it is that you're mixing time-periods, a better example of this is like comparing the modern English speakers to an the Anglo-Saxson speakers from 1000 years ago, while modern English does indeed come from Anglo-Saxon, the two languages are NOT the same, this is what Old English sounded like:
http://www.youtube.com/watch?v=mVyXDYp60BE
Do you understand? No.
Mitanni spoke proto Indo-Iranian language or even proto-Iranic language. Of course there are some similarities between Sanskrit and Mitanni, becasue 2 languages came directly from the same source.
Proto-Indo-Iranian is also a different time-period, the Proto-Indo-Iranian is connected with the Andronovo culture, not Mitanni.
If you say that Mitanni has nothing to do with proto-IE , than you can also say that Sanskrit has nothing to do with IE folks. Because Sanscrit is proto-Indo-Aryan.
Sanskrit clearly comes from Indo-Aryan, Mitanni (Based on whatever words were found), also shares this Indo-Aryan connection, which I should add, was mostly just the names of Gods that were worshiped by the Vedic Aryans (Sanskrit speakers), so in reality, there's no strong evidence on whether the Mitanni spoke an Indo-Iranian at all, but if they did, it would have been comparable to the Vedic Aryans that migrated to India, not the language of the Medes/Persians.
I don't understand why don't you can accept that Kurds are Iranic and related to other Iranics and other Indo-Europeans, from Europe to Central Asia!
I accept the Kurds as an Iranian West Asian people, meaning the majority of their genes are native to West Asia but they carry some Indo-Iranian genes, if anything, I think the ancient Hurrians and other similar ancient West Asian populations probably played a bigger role in Kurdish DNA than the ancient Iranians, this has been proven by the autosomal DNA which shows mostly West Asian.
Somehow you tend to link Kurds only to Central Asians/India, what are your motives for that (agenda)?
I don't try to link the Kurds with anything, but if you were to ask, the Kurds are closer to some of their non-Indo-European neighboring populations such as Turks, Assyrians, Lebanese etc than they are to actual Indo-Europeans such as the Russians or Ukrainians for example, this goes to show you that just because certain groups speak a certain language, it does not mean much in genetics.