I think the Argentina result in the finals of the Copa America made everyone " forget", atleast for a little bit, the struggles we have had with Dunga in command. Before the CA, we struggled in both friendly matchups (Turkey and England). Even before then, we have some games that we struggled in (Ghana, thank god for JC again).
When the CA kicked off, we had an EMBARASSING result vs Mexico. I was in Brazil during this time and everyone wanted Dunga's head on a platter. Next up was Chile (no offense to our Chilean readers), but Dunga's rear end was saved by Robinho, who had an easy time with the Chilean defense. In the final game of the group stage, we beat Ecuador by a Robinho PK.
In the knockout stages, we drew Chile again. Robinho and co. once again was able to expose their defense. Apparently their team was a mess with the whole scandel situation and their incompetent coach. Don't forget that we played Chile in a friendly matchup earlier in the year and we did well in that game as well. In the semis, we drew Uruguay, who usually gives us a tough game. And that is what they exactly did. The game went down to PK's, where we could have easily lost if it weren't from some horrible luck and a questionable non-call against Uruguay. In the finals, we got our rival Argentina. Dunga isn't the type of coach that can motivate our players and get the best out of them, but this game was able to do just that. Our players stepped up without Kaká and Ronaldinho (non-existent players in Dunga's reign) and played good football. It may not have been the beautiful football we are accustomed to watching, but it was effective to beat a top team in the world.
In conclusion, my biggest problem with Dunga is that he lacks leadership. He doesn't know how to motivate the players one bit. I never see him standing near the sidelines yelling out commands to his players or try pushing his players. He just sits on the bench or stands up near the bench and watches the game. He shows his inexperience with his substitutions and game management. Most of his call-ups have been very questionable and he refuses to test out new tatics that could better suit the players he has. Dunga claims that he wants to give opportunities to everyone (his persistence with calling players in Russia, SPFC, etc) but he doesn't do that. He doesn't call up players who are in good form with their club teams. I believe the reason for this may be his ego.