I love reading mystery stories. One of my favourite things is trying to figure out which clues are red herrings. What are the distractions? Which things don’t matter? What gets in the way of important things? It’s not always so easy to see.
It’s not always easy to see which things around the viva are red herrings either. Which things are distractions, and which things should you give attention to?
Hypotheticals are usually not worth your focus; reading your thesis is definitely something to prioritise. You can’t anticipate every question, it’s a distraction to try to – but a mock viva is worth your time so you have some practise at being in a viva-like situation. You can’t know how long your viva will be, so it’s not worth worrying about it; but you can find out about expectations generally to give you an idea.
Remember: you get to choose what you give your attention to. Figure out what the red herrings are, and focus instead on what’s worth your time.