> There is always a professor of distinguished, but long forgotten and superseded past-expertise on the orals.
Wait, are you claiming that knowledge of experimental physics is "long forgotten and superseded"? As a mathematician, I'm all for recognising the importance of theoretical physics, and think that there's no reason a good theoretical physicist has also to be a good experimental physicist—but I wouldn't go so far as casting experimental physics on the dustheap! From the relatively sparse information given, the questions asked, about the operation of basic optical instruments like the telescope and the microscope, do not seem like questions that are excessively recondite; they do seem to indicate a basis lack of competence as an experimental physicist (which Heisenberg neither was nor apparently much wanted to be).