"Preprofessional subjects such as business or law are industrial mass production, with rigour and challenge not created in the classroom but through final exams. (40 % fail rates after 4 to 5 years of law school)."

We have no business exam for the MBA--industrial mass production is the right word. As for the bar, the rates you cite are about twice those in the US for many states (I think it's 80 - 90% pass rate for first-timers).

"Note that the on-average better results for adults reflect solid preparation for the average to above average in secondary school - in Europe, people who are not in stem subjects never see a math class after high school, and vice versa for the humanities."

Well they only need one quant course in many colleges here to finish college--just up through calculus and that's it, if you're in the humanities, so that sounds familiar.

There are certainly pros and cons and you've highlighted many from a first-person perspective and I do appreciate that. Thank you!