That decision was not based on Mirai's Nationals performance though, nor on her body of work. It was based on the politics of dislike and/or not liking some of the skater's choices (the fact Mirai did not have a coach, and that she'd left Frank and had gotten an unfortunate, possibly false reputation for being difficult). Gracie was the favorite, and Polina was the beloved newbie who did not really have any senior-level body of work, nor any exceptionally great junior 'body of work,' aside from junior Nationals.
I agree with everything you wrote. That is why I have a problem with the 'body of work'. It is being used only when they want to, for or against certain skaters.
I am no Ashley fan, and I love Mirai, but I partially understand why they chose her over Mirai. Ashley had contributed a lot to the US getting the spots, she was just one placement behind Mirai, and they had more confidence in her ability to win a medal, no matter how distant that possibility was. Had she placed 7-9 at the nationals, it would have been a lot harder to justify her selection.
My problem was that this was such a rare decision that to me at least, it appeared inconsistent, given that in the past they had sent the podium finishers to the Olympics, so Mirai was understandably expecting to be named to the team. 'Body of work' sounded like an excuse. I also believed that they did not bump Polina because they wanted their own 15 year old who had Russian roots. So imo the judges gave her high marks to put her in second place, making it harder to bump her. I think if anyone was to be bumped for Ashley, it should have been Polina, due to her lack of senior experience. Mirai had been brilliant at the 2010 Olympics. Her Olympic experience should have received consideration.
It is different when a medal winner at the previous worlds cannot compete due to an injury, like Todd Eldredge in 1992. This criterion was well known at the time.
It was different when Michelle was selected over Emily. She was a five time world champion who could not be at the nationals due to her injury. She skated in front of the committee later and proved that she was able to compete. There shouldn't have been any argument against this decision but the media questioned it.
I think there has been more communication about the criteria by the Usfsa, since 2014, so the skaters are somewhat prepared for it, and fans are already arguing about who should or should not be bumped.
My opinion is that they should go with the podium at the nationals, except when a top skater (e.g. Won a world medal in the last two or three years) is injured.