Some of this might be from his Oxford background - Oxford and Cambridge have a very strong culture of small-group tuition, where the tutor ("supervisor") has a

Some of this might be from his Oxford background - Oxford and Cambridge have a very strong culture of small-group tuition, where the tutor ("supervisor") has an enormous amount of freedom. And students typically have end-of year exams -- everything up until that is formative. If you look at it from a semester course-by-course system's perspective it would seem very strangely designed. But Oxford and Cambridge's pedagogy is very effective at producing independently-minded, creative, and somewhat fearless students, who "get" the subject matter. And there is quite a lot of research elsewhere supporting the effectiveness of small group tutoring (which might go a long way to explaining why the Oxbridge teaching style works as well as it does there). So when you say that in his first semester, he gave a great deal of independence to the TAs, especially in small-group discussions, and gave students freedom for all the mid-term testing to be just formative if they wish, that sounds to me as if perhaps he was experimenting with bringing some of what he valued about Oxford's teaching practice to Berkeley.