You are correct that there are surgeons etc that would reply in the negative no matter what was said. My understanding is that if the checklist empowers, say,

You are correct that there are surgeons etc that would reply in the negative no matter what was said. My understanding is that if the checklist empowers, say, 5% of the nurses to speak up and 5% of surgeons to acknowledge the error that is still a huge net positive over thousands of cases. My favorite small nudge example is pill bottles vs "blister" packs. Having pills in blister packs has shown to have a significant effect on reducing suicide as it makes it much harder to get the number of pills needed. Yes, some people will still succeed but there is a segment of the target population who will give up after a couple pills.