Greeks announce national vote on austerity measures. If the vote goes south, eurochaos ensues. Consequently, stock market tanks. Predictable.
But the vote announcement was not predictable. What are the odds that Greece took out short positions in stock market? Now they watch the market succumb.
When it has gone down far enough, earning Greece many billions, there could be a closing of short positions switched to calls and Greece then announces that they are not proceeding with the vote.
Market shoots up, Greece makes many billions on calls.
Thus, the whole world would bail out Greece, not just the European Union. Very smart!