Yanis Varoufakis on Wolfgang Schäuble

There is a thing I have noticed if I have not misinterpreted what I read.
In an article published today on The Guardian, the former finance minister of Greece Yanis Varoufakis has claimed that the intention of Wolfgang Schäuble, the current finance minister of Germany, is a Grexit. As the eurozone is neither a fixed-exchange-rate regime area based on rules and discipline nor a state or a federation issuing its own currency, but a sort of hybrid entity, according to Varoufakis the German minister would see a Grexit as a way to take one of the two paths, that is the path of disciple or the path of an European federation, and, among the two options, Schäuble would favour the “disciplinarian” option rather the federal one (which would be based on mutualization of debt and risk, I suppose, rather than common rules and discipline).
It seems a change of opinion if you compare what Varoufakis itself said to Die Zeit less than two months ago:

Question: What are the European topics you probably could agree on with Mr Schäuble?

YV: That Europe needs a political union and that, without it, our monetary union is problematic.

Substantially, Varoufakis seemed to think, if we stick to his words, that Schäuble was, in his own way, in favour of a political union, rather than of one simply based on rules established and followed by national governments. Today, Schäuble is included in the camp of those who do not want a federation. Since to me political union and federation are quite synonyms, at least in European Union matters, that seems a shift in opinions.
Furthermore, what Varoufakis wrote today (that a Grexit could have two possible outcomes, one of which would be a federal Europe) leaves room for some interesting reasoning on what a European federalist should wish in order to achieve his/her political target. What if the sacrifice of a member state could lead to the unintended consequence of a European federation, based on the urge to avoid the same scenario in the future? Could be a good idea to sacrifice Greece and ‘upgrade’ the rest?