Guy’s tutorial rearranged with no need (12)

I believe the answer is:

gratuitously

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'guy's tutorial rearranged with no need' is the definition.
I can't judge whether this definition defines the answer.

'guy's tutorial rearranged' is the wordplay.
'rearranged' indicates anagramming the letters.
'guys'+'tutorial'='guystutorial'
'guystutorial' with letters rearranged gives 'GRATUITOUSLY'.

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I've seen this clue in The Sunday Times and The Times.

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