Of course, much depends on the teacher's philosophy and pedagogy. Schools Without Failure, and The Quality School are two best-sellers. I would hate to drive over a bridge, work in a building, or fly in an airplane designed by engineers who depended only upon memory.
Engineers utilize handbooks and tables to look up important but hard to remember details.
In my medical training, I have seen experienced surgeons call for a surgical book to be brought to the operating room when they were faced with an unfamiliar situation. I have seen other surgeons, products perhaps of too many closed-book tests, go ahead and continue to operate when they weren't sure what they were facing, at times to the extreme detriment of the patient. The world says look it up, don't rely on your memory. Schools say look it up, but rely on your memory any time it really counts, preparing students for a world that doesn't exist. Tests are not supposed to prepare us for this rare occasion.