Despite his well-earned reputation as a bratty cabrón, there's reason to believe Macri will fold on certain issues if enough people keep up the pressure - especially if said pressure comes from the well-connected.
Take higher education:
During the runoff campaign the National University Council (CIN), a roundtable of college presidents and dean from across Argentina, endorsed Scioli for President. Their reasoning was simple: public higher education budgets had tripled in real terms during the Kirchner era, 15 new public colleges had been opened, thousands of academics had returned from Spain, enrollment was way up, and so on. For them it was a simple question of rewarding a good record.
But that's not how the touchy Mr. Macri saw it: for him it was a personal slight. His reaction? He nominated a talk show producer, Juan Ávila, as Secretary of University Policy - the first non-academic ever named to the post, and as you can imagine a very deliberate insult against Argentina's 170,000 college faculty staff. The fact that Ávila is the son of the founder of a sports channel controlled by the Clarín Group added a good whiff of corruption to the already unpresidential motive.
What Macri did not count on, was the clout academics have in Argentina when they're united and the public outcry against the nomination of the decidedly unprofessorial Mr. Ávila - a man who could have easily been cast as one of Rocky Balboa's trainers (with apologies to Burt Young).
After a few days of that, Macri relented. Save the photo, as they say, because that doesn't happen too often.
The point of the story is that when the heat is on, Macri prefers the shade. As with the ongoing human rights trials, the only way Macri will keep faith with this agreement is if the international community holds him to it.