NSW banker affected motorist? (4,6)

I believe the answer is:

twee driver

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'nsw banker' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'affected motorist?' is the wordplay.
'affected' becomes 'twee' (I've seen this before).
'motorist?' becomes 'driver' (motorist is a kind of driver).
'twee'+'driver'='TWEE DRIVER'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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