You can call it a test, a rollout, a phased implementation, a temporary program, a transition, or whatever you want. To me, that is all semantics.
I just think what Disney is going through now is an essential part of putting the whole MyMagic+ (not just FP+) system into full effect. First, they have to test the mechanics of the system to see how it performs. With respect to FP+, they have to test guest behavior before making decisions about the details of the program, such as how many FP+ reservations everyone should get, whether to limit reservations for headliner attractions at some parks, how many reservations to allow per hour, etc. They have to be using the test to see how many guests actually make advance reservations, which attractions they choose, whether they tend to make reservations early or late, whether they make same day changes, and how many of the reservations go unused, etc.
I suppose Disney could announce parameters now, but they would all be subject to change anyway if actual usage proves that they must change. I don't think guests would be any happier with that than they are with the transition that is going on now.
The decision to try giving guests MB only with no backup cards tells me that they are satisfied that the number of problems people are experiencing with the bands are manageable. So, now they are gradually beginning the process of weaning guests from using cards at all.
I do sympathize with people who feel like their ability to enjoy their vacations are being adversely affected by this transition. Just like I sympathized with people whose only Disney trip came during the height of the Fantasyland construction and they had to look at a lot of construction walls. But, in my opinion, a transition like this is necessary to implement some new technology that I think will make guest experiences better. We experienced some of that improvement on our brief visit last week, and that makes me more confident that we, and the majority of other guests, will like the end product if we are patient enough to let the process play out.