[EM] Strategy in Condorcet methods

[Kristofer Munsterhjelm]

When I was exploring three-candidate linear Condorcet methods, I noticed 
that the most strategy resistant methods did not pass both monotonicity 
and reversal symmetry. The best result I got for methods that passed 
both were susceptibility to strategy around the 70% range, where Minmax, 
Ranked Pairs, Schulze etc is around 75%, and Smith,IRV is around 12%.

So perhaps there is an impossibility theorem hiding somewhere that says 
that a Condorcet method can't pass monotonicity, reversal symmetry, and 
some criterion that confers strong worst case strategy resistance. Of 
course, it's hard to say anything at all without knowing what the latter 
criterion *is*.

But this train of thought got me thinking about the Chicken Dilemma 
criterion. Perhaps that is one such criterion. And if so, do any of you 
know a method that passes monotonicity, reversal symmetry, and the CDC? 
Or of a possible strategy towards an impossibility theorem showing that 
one can't have all of them?