No, not entirely.
He can't pitch the ball, he doesn't go up to bat and he doesn't take the field and he didn't get to handpick his personnel. And yes, his lineups cause more controversy than anything and you could certainly say that's hurt his cause. However, what I blame Dusty for is not getting the most out of his players, which is supposedly his specialty. I remember last year, the Cubs got off to a bad start. What did Sweet Lou do? He goes on a tirade and gets ejected and mysteriously, the Cubs played much better from that point on. Many Cubs were cited as saying that it was a turnaround point in the season for the team. Why is it that the Pirates are contending this year with less talent and playing the same schedule as the Reds? You could debate the talent I suppose, but a big part of it is the fact that those guys are relentless. They have tenacity and they look like they want to win each time they play.
Good managers motivate and light a fire from underneath when the team needs it. Good managers get the most out of their players and don't allow for complacency. It's almost like Dusty knows he's got a big payday for 3 years, so he's sort of nonchalant about everything. I'm not suggesting he's happy about losing, but I do think he's not taking it very seriously and he seemingly has done nothing to try to improve the situation. This team has many flaws, but there are no stats/metrics or anything anyone can tell me that would have me believe that this team is giving 100% effort. 100% effort may not put this team in contention, but it would sure help them get closer to it. And for this, I blame the manager.