[EM] Conditionality-by-top-count probably violates FBC

[Kristofer Munsterhjelm]

On 02/19/2012 09:37 PM, Kevin Venzke wrote:
> Does anyone understand why the DH3 concept exists? Why envision three
> major blocs, instead of two major blocs plus the small bloc belonging
> to the pawn candidate? That doesn't require four candidates and more
> closely resembles how burial problems are usually considered...

If there are just two blocs, then the DH3 scenario never gets off the 
ground. Say you have a nobody, Z, and two viable candidates (A and B). 
Then say the honest ballots are something like:

53: A > B > Z
46: B > A > Z
  1: Z > A = B

Then the B-supporters can't get the ball rolling, at least not in 
Condorcet, by burying A. Even if they do so, A will win by first 
preferences alone.

Technically speaking, it takes three viables to make a cycle, and you 
need cycle-making/turning strategy to make DH3 work in Condorcet. In 
Borda, you could do a sort of DH3 with only two blocs, but that's 
because Borda doesn't satisfy Majority.