“I don’t know” is a brave sentence in a room full of people pretending.

Most rooms run on a quiet agreement that everybody understood the thing. Admitting you did not breaks that agreement, which feels dangerous and is usually a relief, because half the people nodding could not have explained it either. Saying it also makes you the person whose yes can be trusted later on.

Use it once this week instead of nodding. I do not know, can you explain that part. Then notice how many others lean forward. The only people who lose standing by admitting a gap are the ones who never close it.