It's pointless to argue or deliver your inspiration (4,4,6)

I believe the answer is:

save your breath

I'm a little stuck... Click here to teach me more about this clue!

'it's pointless to argue' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'deliver your inspiration' is the wordplay.
'deliver' becomes 'save' (saving is a kind of delivering).
'inspiration' becomes 'breath' (I've seen this in another clue).
'save'+'your'+'breath'='SAVE YOUR BREATH'

'or' acts as a link.

Can you help me to learn more?

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

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