Balance up, etc, in error; it won’t do! (12)

I believe the answer is:

unacceptable

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'balance up etc in error it won't do' is the definition.
I can't judge whether this defines the answer.

'balance up etc in error' is the wordplay.
'in error' is an anagram indicator.
'balance'+'up'+'etc'='balanceupetc'
'balanceupetc' with letters rearranged gives 'UNACCEPTABLE'.

Can you help me to learn more?

(Other definitions for unacceptable that I've seen before include "Not satisfactory" , "Not allowable" .)

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

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