Perhaps I'm blind, but I just don't see how this all should be the case
at the same time. Could you please give a concrete example of such a
situation?
Imagine these sincere preferences. (I'm just "telling a story" here, these preferences are not part of the "real" example.)
49% C>>B>A
12% B>C>>A
12% B>>A>C
13% A>B>>C
14% A>>B>C
A simple linear political spectrum, with B as the centrist, and the Condorcet winner. Now, imagine many of the CBA voters have strategically upranked A (with some of them approving A as well) in order to create a cycle. Here is the "concrete example":
10% C>>B>A (the "honest" ones)
23% C>>A>B
18% C>A>>B
12% B>C>>A
12% B>>A>C
17% A>B>>C
10% A>>B>C
B>C 41% approval
C>A 61% approval
A>B 45% approval
Now, imagine you are in the 17% A>B>>C faction, and you are aware of the situation. The only way you can prevent C from winning is by insincerely disapproving of A.
10% C>>B>A
23% C>>A>B
18% C>A>>B
12% B>C>>A
24% B>>A>C (including 12% insincerely disapproving of A)
5% A>B>>C (the "honest" ones)
10% A>>B>C
Now A's approval (33%) is lower than B's (41%), which allows B to win the election.
There is a rather large set of situations where this can occur. I constructed this one to be what I saw as a plausible situation where insincere order-reversal and disapproval was clearly a superior strategy.
In winning votes, the ABC faction can simply equal-rank. At this point I'm fairly convinced that measuring defeat strength by winning votes more reliably avoids the need for favorite betrayal, compared to measuring by winner's approval.
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