A Simple Example

 A
A
B
B
C
A
C
B
C
It is pretty clear that under just about any method, the overall winner is going to be either A or B. Using plurality or run-off, B is the winner. But we have decided to use Borda. When we add up the points, we find:
A: 
23 points
B: 
22 points
C: 
3 points
Close, but A wins out using Borda.

So here's an interesting question: how important is C in this example?