In 5 False Assumptions Political Pundits Make All the Time Molly Ball analyses work published by political scientist Morris Fiorina. The five false assumptions are:
1. The electorate is not "polarizing." It's "sorting."
2. Candidates change more than voters do.
3. Independents aren't partisans.
4. "Division" is easy to overstate.
5. Campaign ads really, really, really don't make much difference.
This is an American article and the rules reflect the US political system. However some of it holds true for Australia. Worth a read.