I will give you that your example demonstrates that if your choices alone were to decide the outcome, a system that only ranks the candidates can be somewhat insufficient.
However, let's assume that the ranking system in question allows you to, rather than flipping a coin, simply rank A and B equally. In other words, declare them a tie. Now, since your ballot is *not* the only one that decides the outcome, the other voters will make your decision between A and B for you, exactly as you wished. It does what you want, only in a far more straightforward way. Instead of allowing you to vote for a choice based on the votes of others, it simply allows you to defer to others things that you would rather not decide yourself. It is almost like you are insisting that you be able to explicitly vote for whoever wins, rather than just not vote. What is the point? ---- Election-methods mailing list - see http://electorama.com/em for list info