There is a similar story -- whether true or not I don't know -- told at Oxford about Cambridge and at Cambridge about Oxford. Someone wrote a thesis on anti-metric spaces, which are like metric spaces, except that the triangle inequality is the other way round. He proved all sorts of interesting facts about them, but at the viva, the external examiner pointed out that there are only two anti-metric spaces: the empty set and the one-point set.
It is recounted that the student passed, but his supervisor was criticised for not having picked up on this earlier.
Likewise there's the story about the Princeton student defending his thesis on the set of real functions that satisfy the Lipschitz condition for every positive constant C, and being asked by an examiner to compute the derivative of such a function...
My point having been, of course, that the k-quandle story is not (necessarily) of this type.
A monthly thread for posting rationality-related quotes you've seen recently (or had stored in your quotesfile for ages).