I have to say that I am rather surprised (again) at the poor judgement Rootsi's team (who includes such famous population geneticists as Myres, King, Balanovsky, Behar, Battaglia, Semino and Underhill) when it comes to linking subclades with historical events. For example:
1) They only associate haplogroup G with the spread of agriculture, with no mention at all of the Indo-European migrations.
2) They associate the G2a3b1a1a1 (G-M527) lineage with the Greek colonization, when it is found in places that have nothing to do with the Greeks, such as Estonia, Belarus, Tatarstan, Iran or Germany.
3) They associate G2a3b1a2 (G-L497) with the LBK culture, which is really startling since there is close to no geographic correspondance between the two.