One of the biggest mistakes Greece repeatedly makes when holding international level talks is believing that the mediators and negotiators involved are all playing some kind of game and serving their own nefarious needs. What this results in is personal attacks being launched against the interlocutors, sometimes slanderous.
Not only is this tactic counterproductive and naive; it can also be very dangerous. The representatives of big powers or international organizations rarely deviate from the line set by the institutional interests they serve.
Casting them in the role of villain may appease the public at home and may sound convincing to some, but it creates enemies for no reason whatsoever and makes Greece look ridiculous.
Tough negotiations should never involve personal confrontation and meaningless chest-thumping. Greece has scored some of its greatest victories when it has presented itself with confidence and when it has kept its friends and allies close.