Varoufakis' plan, as outlined here in an interview in The New Statesman, was never embraced by Syriza as it needed to be to have even a chance of succeeding:
[Yanis Varoufakis] said he spent the past month warning the Greek cabinet that the ECB would close Greece’s banks to force a deal. When they did, he was prepared to do three things: issue euro-denominated IOUs; apply a “haircut” to the bonds Gree[ce] issued to the ECB in 2012, reducing Greece’s debt; and seize control of the Bank of Greece from the ECB. ... As the crowds were celebrating on Sunday night in Syntagma Square, Syriza’s six-strong inner cabinet held a critical vote. By four votes to two, Varoufakis failed to win support for his plan, and couldn’t convince Tsipras. He had wanted to enact his “triptych” of measures earlier in the week, when the ECB first forced Greek banks to shut. Sunday night was his final attempt. When he lost his departure was inevitable.
