> Without pressure from grades, [students] won't do the work of learning.
If it were qualified with ‘many’ students, there would be no such confusion. Your comment, as-is, is trivially falsified by the example of any auto-didact.
That's not how the English language works. The reason the adjective "all" exists is strong evidence that when one says students (plural) one is not saying "all" students.
If one meant "all" students, one would say "all students", "students without exception", "100% of students", "every student", etc.
"Among the requirements for the major are successful performance on a junior qualifying examination, completion of a yearlong senior thesis based on original research or artistic expression, and a successful oral defense of the thesis before an interdisciplinary faculty board."
I was answering a question about grades, not tests.
Also "demonstrate rigor" absolutely does not imply tests. In my undergrad (math) the level of rigor of tests was uniformly (and necessarily) much lower than homework and other assignments without the same time pressure. I would expect the same to be true in many other fields.
Pass/fail is still a grade, albeit a binary one. Caltech had pass/fail for freshman, and still most everyone felt the pressure at the end of the semester with the final exam looming, and worked hard to pass it.
> Also "demonstrate rigor" absolutely does not imply tests.
I didn't say "all students".
> a number of colleges and universities that don't use grades
An example of a prestigious university that doesn't use grades would help your case.