It is amazing how quickly you forget things that once were self-evident. In American universities, classes are taught either on Monday-Wednesday-Friday or Tuesday-Thursday. Everybody knows this. If I hadn't known, or rather hadn't retrieved it from the deepest corners of my memory, I would have problems decoding the casual referenses here. I used to prefer Tuesday-Thursday because the Monday-Wednesday-Thursday sessions are too short for a reasonable discussion. But in fact it is no more and no less strange that in Cambridge, we always teach part-time students on Wednesday afternoons. Everybody know this!
I keep saying "in Cambridge, we..." about things that two years ago felt weird. Team-teaching is the most natural thing to do now. How can it be otherwise? How can students take several classes at a time? How can possibly an instructor mark her own students' work?
I recalled yesterday, in a conversation with a colleague, the expression "freedom of the classroom".
And no, I am not saying that one is better than another. It's just that you get used to something and then you forget. Just as you forget Fahreheit if you don't practice.