The view back from 2021: How the euro was saved With a bang, not a whimper

Mr Berezin's ( of Bank Credit Analyst) June report accurately pinpoints the source of the crisis: persistently higher inflation and slower productivity growth in the periphery led to growing current account deficits with Germany. (emphasis added)

Thus The Economist (Free Exchange) 25/07/12 endorses Berezin's diagnosis.

I humbly agree, also. BUT one key reason for that development was the lower than appropriate interest rates for the periphery to accommodate German conditions.
See Fernanda Nechio of the Federal Reserve Bank of S.Fransisco.
Another good expo is referred to by  Yves Smith over at EconoMonitor