papandreou's reason for a referundum, page-5

Not my opinion, survey data:

UK POLL: 78% of respondents think Greece should leave the Eurozone. (HuffPost UK)

Greek POLL: 70% of Greeks want to remain in Eurozone, but tolerance for austerity has limits. (The Economist)
Perhaps that what people really want.

Leaving the above aside - my question to the the resident economic experts:
Current wisdom is that Greece should
a) default
b) leave the EU,
c) devalue its currency
d) regain competitiveness and export its way out troubles.

Greece has never been an 'export' country. Its exports to GDP is about 8%. During in its entire modern history, Greece has survived on EU transfer payments. That is an economic fact.
Due to the crisis, Germany has agreed to continue the transfer payments indefinitely, but not the IMF.
So in reality, there is very little difference for Greece:
a)if stays in EU - Germany pays or,
b)if leaves the EU - IMF pays.
The question is: on what basis economists argue that Greece would be better off by returning to the Drachma, i.e. devaluing its currency to regain its competitiveness and export its way out of austerity?

Yes, i know - it makes good political headlines as opposed to economic arguments:-).IMHO