"I think DD was released for that purpose, for the tour.. so the tour wouldn't seem completely random, in other words the tour was not really made to promote the single but only made to look like it was."

There's really no way in knowing this, but having Mike Rizzo make a mix of DD and include him in the tour makes me lean the other way. I don't think Utada is opposed to doing random tours and don't think Rizzo would be in the tour if it wasn't to promote DD, and she had a break at the end where she asked everyone to request DD on radio even though she doesn't listen to radio; her words paraphrased.

"after she got sick, I really think that utada was very insecure and unsure of what she wanted to do. I think that not only her but also IDJ thought that the prime time for her to promote the album, which was after its release had long passed. BUT before completely giving up on the album i think they wanted to have another round, to see if they could "revive" it, thus the tour."

Again this is coherent with the other facts, but I don't think the tour was "a litmus test." Did you go to any of them? For the venue it was amazing. They put a lot of effort in this tour, especially if it was just to see her American fanbase.