Please explain the curve to those who must use it!

We're graded on a curve. They tell us that's university policy and each class has gone over how it's going to work in their class.  (Not that they actually help explain what a curve is and how it works - so many students are still completely mystified by the concept, but I digress)

The basic premise is that our grades are compared to the mean - and thus we are compared to each other rather than some other standard. This is supposed to help even out the difference between the sections caused by different teaching ability and grading of exams and assignments.  Fine.  I accept this, I almost even like it. 

However, no one has explained how it works to one of our profs.  The whole point is to differentiate the grades so that you can rank people. 

We have a class that has 3 assignments each with multiple parts.  The weighting of these add up to 100.  that's pretty normal. But I'm going to explain how the 1st assignment has broken down.  There were 5 parts each worth 5 points.  The 1st was a survey about our feelings towards various topics that were to be covered in class.  He finally decided that if we had done it - we'd get 5/5 and if we didn't we'd get 0.  But he was "generous" with the deadline so that people had a chance to hand it in after he made this decision.  Then he released the "rubrics" for the other 4 parts.  There were options for 5/5, 4/5 and 3/5...  If you fucked it up, but still handed it in - you get 3.  If you did the assignment completely you get 4.  And if you have one of those "shining stars" "blow his mind" assignments - you *might* get a 5.  But, he seemed pretty skeptical that any of us lowly peons could achieve such a thing. 

If you've been following along, you will see that if you did the 5 parts you will end up with 21/25 for assignment #1.  If you were a COMPLETE idiot - you might end up with less.  If you failed to hand one part in - then you're fucked! 

What he's effectively done is have an assignment that does NOT differentiate the students in the class.  If almost everyone gets the exact same grade - then the assignment us useless for creating a curve.  It's a spike!  And that assignment was pointless for the purpose of assessment.  You could argue that we learned from it - so it still has value - but then you've likely not read the assignment.  It was simply a fap fest where the same questions were asked in a variety of ways. 

So - now we have a class that's out of 75 points.  Fine.  But - then why not state that at the beginning.  This has increased the weighting of all the other assignments.  The ones that are group work and worth 60/100.  So the massive group project has gone from being worth 60% of our grades to  80% of our grade.  And our meta-reflection (does that term make anyone else giggle?) has gone from 15% to 25% of our grade. 

Assignments that don't create a range of grades are pointless on a curve.  Well...  I guess they mean that the poor sap who missed one is going to get a D in the class.  So I guess that's good. 

Can you tell I'm frustrated?  At least they've now all been graded 3 weeks after they were submitted...