While criticism in good faith of decisions of European institutions, including the ECB, is indeed valid and useful, decisions which provide fertile grounds for backtracking on European integration are rather harmful.
The ECB needs to be able to continue designing and implementing monetary policy for the entire euro area, taking care for the smooth functioning of the transmission mechanism and tackling fragmentation in financial markets. Allow me to conclude by quoting Aristotle, who said «τοὔνομα ἔχει νόμισμα, ὅτι οὐ φύσει ἀλλὰ νόμῳ ἐστί». The currency is based on the Law.