[dragonwriter]

> Bottom line - this seems interesting, but is hardly as simple as "all ranked voting systems can be gamed"

It is almost that simple. Every deviation from the unattainable ideal in Arrow’s theorem corresponds to one or more ways that the system:

(1) can be gamed, or

(2) is insensitive to voter preferences, or

(3) changes outcomes in the opposite direction of changes in expressed voter preferences.

(And usually several from multiple categories.)

There are whole catalogs of these and enumerations of which ones apply to each voting system.