Limits of Control
You’re not in control of your viva and the situation around it. You’re not totally out of control either.
You can’t control who your examiners are, not directly…
…but you can control what you know about them through research before your viva.
You can’t control what questions they ask or what they think…
…but of course, you will influence them with your thesis.
You can’t control how you will feel on the day…
…but you can control what you do in preparation, where you focus, how you get yourself ready.
You couldn’t control everything that happened over the years you did your research…
…but time and again you could steer yourself, change direction when needed, make small adjustments, and lead yourself to where you are now.
Which means, I think, that even if you can’t control everything about your viva, you can do enough to get yourself through it.