Some vivas are less than an hour!
But you can’t realistically expect yours to be.
You can hope, but what does that do for you?
It’s much better to prepare for your viva and the discussion, rather than invest energy in hoping it will be over quickly.
PS: Something else that’s short and sweet is my helpful little guide, 101 Steps To A Great Viva! It’s on Kickstarter until Wednesday 31st May, raising funds to produce a print run. That goal has now been reached and I’m aiming a little higher so that all backers get a bonus resource for viva prep. You can find more details at this link.