I don't mean any personal offense to you, Jung, but maybe the real plan is not to be as blindingly stupid as they were last year by pencilling one and exactly one reliever into each role and saying "closer. Right. Got that one. Now on to set up. Melancon? Fine. Now, who's our middle relief?" With the result that Aceves wound up shoehorned into the closer's role because of inadequate planning and depth.
1 closer and 2 setup men is about right, and having 2 of those guys be steady durable arms doesn't hurt. If Bailey can contribute, great, if not, we're prepared to work around that with Hanrahan, Uehara and possibly Tazawa. And we have a couple guys below them not named Aceves, who could do in a pinch if called upon. Breslow has played some leverage relief before, and Miller and Morales (as well as Tazawa) are worth trying. And who knows? Bard may be a bit less dead than we think he is now.
The point is that they're thinking ahead and making sure we have options. Depth and resiliency. It's a good thing.