Moondoong, Going back to the Drachma would be all but impossible. Consider the mechanics; Tourists and locals would prefer Euros so they can buy imported goods. Greeks would have to turn their bank accounts from Euros to Drachmas, at what exchange rate? Greek debts would have to be repaid in Euros.
I think the solution is easier. Greeks need to pay tax, sack public servants, sell infrastructure and lower wages like the rest of Europe.