Sanctions a writer; is adding two points (10)

I believe the answer is:

authorises

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'sanctions' is the definition.
The definition and answer can be both to do with communicating as well as being verbs in their -s form.
Perhaps there's a link between them I don't understand?

'a writer is adding two points' is the wordplay.
'a writer' becomes 'author' (synonyms).
'adding' means one lot of letters go next to another.
'two points' becomes 'es' (two compass points).
'author'+'is'+'es'='AUTHORISES'

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(Another definition for authorises that I've seen is " Gives the OK".)

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

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