This is quite a good read. I see both sides of the argument to be honest.
I favour incorporating a viva for the simple reason I think it forms an important part of assessing the student's true knowledge of their subject, though her views are interesting.
I'll admit could be argued that if a thesis / dissertation is exceptionally good and the academic excellence of the candidate is clear, then is a viva actually needed when it's clear the candidate is going to pass?
Ian