I used to teach physics to pre-med students (a nearly-identical situation to [2] in the original post). I tried to write my exams so that simply memorizing a large set of very specific algorithms for solving a problems wouldn't work, but nobody would have to be very clever in order to get a good grade.

In addition to this, I looked at the course material and asked "Is there anything thing on here that a doctor really needs to know?". I decided it was good for doctors to know how half-lives work, since this is important for things like drug dosing, as well as probably other things I don't even know about (since anything who's rate of decay is proportional to it's value will behave the same way). So, I explained to my students that a discharging capacitor was mathematically identical to the way that some drug concentrations decrease over time, and that there absolutely, positively would be a question about it on the exam. I didn't say anything else very specific about what would be on the rest of the exam. That exam had one question about a discharging capacitor, followed by a second question that was the same as the first, but reworked in terms of drugs. Most students got the first one right, but fewer got the second.

I think that part of my distaste, as an instructor, for students knowing a lot more about what is on the exam was that I wound up talking a lot more about the same things, and it got boring.