As a current student, I can confirm your suspicions about a seemingly complete paper being preferred over one that addresses all information about the topic. "I don't know" still is not an acceptable answer in many circles and I regard it as an unfortunate phenomenon.
In my second year uni course, I have an outline for writing lab reports that
says 'include in your discussion anything you feel is out of place, or that you
don't understand in this experiment. You will not be marked down for such
admissions'. And I thought 'NO-ONE is going to take you up on that.'. I hate
having to bullshit science papers - I tend to compromise, with a hashed together
explanation that I express doubt in, and take the marks hit. Bullshitting is
great fun in English courses, but in science it feels like shooting myself in
the foot.
As a current student, I can confirm your suspicions about a seemingly complete paper being preferred over one that addresses all information about the topic. "I don't know" still is not an acceptable answer in many circles and I regard it as an unfortunate phenomenon.