[gumpzilla]

The professor doesn't necessarily have to be bluffing. You're neglecting how stupidly obvious it frequently is that people have cheated. Here are a couple of examples:

1) A friend of mine when TAing got one of the weekly quizzes back. Two of them had identical handwriting; the sole effort made to disguise the handwriting was that on one quiz the student wrote all of his Rs backwards, Toys R Us style. The answers were exactly the same and horrendously wrong.

2) I was grading homework for a course at one point, and found that the other TA had prepared solutions with numerous errors - four out of thirteen questions were answered incorrectly. I received three assignments that were entirely correct except for those four problems, where the exact same mistakes were made. After I asked the students about this, one of them actually said to me, "Well, it never explicitly said that we couldn't copy the solutions for the homework assignments," which, while technically true, seems pretty excruciatingly dumb.

I also think that what I find more bothering than the cheating discussed here is the amazing amount of rationalization and justification of it. Do what you gotta, I guess, but I can't believe how many of you seriously seem to think you're in the right here.