I don't know what you think you proved, or what I need to retract. I know what the ceremony is. I've also been pretty consistent that there's "a time and a place" for public protest.
And yes, college campuses have long histories of being fertile ground for protest, and that is as it should be. The university did the right thing by not cancelling a speaker because of her personal views.
However,
the University was also correct when it released this statement:
“The University of Michigan does not revoke an invitation to a speaker based on their personal beliefs,” Masson wrote.
“However, the White Coat Ceremony will not be used as a forum to air personal political or religious beliefs; it will focus on welcoming students into the profession of medicine.”
Dr Collier respected the ceremony for what it was: recognition for the dedication that it took, and will continue to take, for students to enter the world of clinical medicine. These students who got up and walked out did not: they tried to turn the event into a pro-choice protest. Sure, Collier is pro-life. But she wasn't selected to speak because of her pro-life stance and the event was not about abortion rights. So, for the students to inject their personal politics into a non-political event is shameful.
On the other hand, if the event was a pro life rally on campus and these students wanted to protest there, by all means have at it. That's the appropriate time and place to make your point. But a white coat ceremony - which has nothing to do with politics - is not the appropriate time and place.