Personally, I am not a big fan of central bank independence, as a concept. There is always some dependence, because institutions are staffed and constructed by humans, and I think proclaiming independence is a bit muddy in democracy. If Tsipras took control over Greek Central Bank, it would still have greater democratic legitimacy than the control Eurozone leaders have over ECB (the fact they have some I think can be seen from the fact that ECB didn't provide liquidity to Greece before the referendum - really independent CB in a monetary union would have to do that anyway and let the politicians face the consequences).

(I am really torn here, because, even though I wish Eurozone to succeed, sadly, the existence of EZ and ECB was not established in a democratic process, as it should.)

The idea that a parliamentary decision would have been better than one from the cabinet because the legitimating chain would've been slightly shorter sounds like a rather esoteric reason to judge their actions on.

But as opponents this is a great opportunity. They'll get crushed, I guess.