Sparkey, I respect you 'coz you're one from (not so many) "normal" people here :) You're trying to judge problems with the scientific facts, not with some kind of myths.
If Nordtvedt is right, then there's no other explanation than Slavic expansion. There's a very interesting Turkic ethnic group in Moldova- Gagauzes
http://www.joshuaproject.net/people-...=11798&rog3=MD
Well... we know now that we don't have I's outside Europe. That means only one thing- 30% of I2a1-Din-N in Gagauzi people didn't come with Pecheneges but they are assimilated there.
It is a similar situation like with Hungarian nation today. More than 50% Hungarians belongs to R1a/I2a as their Slavic neighbors. Probability that these I2a-Din came together with Atilla from Asia is lower than 0.001% On the other hand, we have Bulgarians who remained their Slavic language but they adopted name which isn't Slavic by origin. That I2-Din-N could easily belong to the (today's) Bulgarian tribes which lived there up to arriving of Bulgarians from today's Russia.
South Slavs (Din-S) obviously had a "baby boom" in the past. I2a-Din-S wasn't so numerous in the period when they arrived in Balkans. Even more, that Din-S is the same for today's Serbs, Bosniaks and Croats.
It is not a secret now that tribes which were dominantly I2-Din-S came firstly in today's Bosnia (which were part of Roman province Dalmatia), and even more precisely, in Herzegovina. They dispersed themselves to the eastern parts of Croatia and western parts of Serbia.