Fit from doing nothing out of the ordinary (2,4,4)

I believe the answer is:

in good form

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

'fit from doing nothing' is the wordplay.
'fit' is an anagram indicator (letters fitted or arranged in a different way).
'nothing' becomes 'O' (looks like zero - 0).
'from'+'doing'+'o'='fromdoingo'
'fromdoingo' is an anagram of 'IN GOOD FORM'.

'out of' acts as a link.

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I've seen this clue in The Globe and Mail.

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