I am not sure what to make of your first point, as it is not clear that we (HN) have a common understanding of what is meant by "fragmented". Is it a government which does not pass laws or spend money on specific programs which different groups oppose for varying reasons, or would that be a unified opposition? Would fragmented government pass a great many laws and spending programs with no unified goal, to appease disparate interest groups, or would this be a coalition?

>Distinction without a difference. Even if the focus is on the candidates, they're all firmly partisan with little variation.

Does it matter whether the politicians are partisans unified in party goals? It seems that in the USA, politicians frequently go against their own parties, relative to other countries. Is partisanship in favour of non-party aligned interest groups part of what you perceive as a problem? Please describe a non-partisan politician, party, or system.

Lastly, I think we can all agree that a single anecdote does not make the case for or against the PR system, though it does show that PR is not a sufficient condition for stable and everlasting democracy.