“Can you explain how to make a genus 2 handlebody?”
I was really confident on the results of Chapter 5, but the background was shaky at best in my mind. I had a great result, proved an open conjecture, but couldn’t explain the background with confidence.
And I knew it. I knew it as I was reading my thesis and making notes in prep for my viva. I knew what the worst question was just from reading my thesis. I could have spent more time trying to unpick it and prepare. Instead I hoped it wouldn’t come up.
In workshops I’m regularly asked, “What’s the worst question that your examiners could ask?” It varies for every person. I think each candidate knows what the worst question is, because they’ve already encountered it. In preparation for the viva it’s an area to definitely spend time on. Don’t just hope it won’t come up.