Oh, I just know they opened that particular show in Denver with To the Bone because I found myself watching the intro video, recorded at that show, on Facebook the other day. The video went on long enough for the first song to have started. I don't know why they chose to open with To the Bone that night, all I know is why they originally stopped playing it as the regular opener.
Going back to the intro video on Facebook, I was amazed how engaged the US audience was in all the headings that appeared. The audience in the UK was silent throughout each of the four shows I attended, save for the first scientology reference where there was a brief titter each time