Viva voce question about another student "validating" my results My PhD supervisor wanted me to talk about how my research was "validated" by another student in my Viva Voce, despite my results speaking for themselves. This part of my findings had not even been questioned by my examiners.

The student in question had never worked with me in any way. Nor have they published in a work I could cite - conference paper, article or even blog post. Or even private correspondence.

He claims it is common to "have worked with people in this way".

I don't understand why he would ask me to do this.

Ideas?

Post-script:

I am asking this question from the perspective of the exam administration. 
Isn't it cause for concern to bring up a person who wasn't cited or acknowledged in the thesis during the Viva?
I suspect your supervisor was thinking about how that student confirmed your results. A classic way this could happen is, if you solved a problem with one method and then the other student solved the same problem with a different method, and your results agree, then the other student has "validated" your results. Naturally, you don't need to have worked with each other to do this - in fact it's arguably preferable that you don't work with each other, to ensure independence of results. Neither do you need to be able to cite their work (you can just say "unpublished").

It's always good to have someone validate your results, because it increases the chances that your results are robust and not due to, e.g. statistical noise. If someone has validated your results, it's definitely something to mention.