MDDA and MAMPO (if modified to allow voting an Approval line instead of saying that all ranked candidates are approved) share UncAAOs advantage of a majority being able to make a candidate lose while still ranking him. But, since its necessary to know to not approve him, its not as if no strategy is needed.
UncAAO, ASM, and DMC ignore defeat-magnitude and magnitude of pair-wise opposition. They look at pair-wise vote totals in order to find out who beats whom, but then they throw pair-wise vote total information away. Throwing that information away has regrettable consequences.
As exemplified by my majority defensive strategy criteria, its possible to make some guarantees to a majority that couldnt be made to a smaller group. So its desirable for a method to be able to recognize a majority.
An Approval count can recognize a majority. If a majority approve X but not Y, then theres no way that Y can win. Thats why MDDA and MAMPO meet SDSC. And maybe so do some or all of the other methods listed above.
But what if youre interested in not having to use any strategy at all under certain conditions. Then Approval strategy is out. Then its about rankings and pair-wise preferences. To recognize a majority pair-wise preference, its necessary to look at pair-wise vote totals, other than just to find out who beats whom.
Thats why UncAAo, ASM and DMC dont meet SFC, and dont offer the freedom from strategy need that SFC confers under plausible conditions.
Mike Ossipoff
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