Old fogey, doctored, needing particular set of sheets (6-6)

I believe the answer is:

square-rigged

'needing particular set of sheets' is the definition.
(of a boat requiring certain sheets or sails)

'old fogey doctored' is the wordplay.
'old fogey' becomes 'square' (both can mean an uncool person).
'doctored' becomes 'rigged' (both can mean falsified or manipulated).
'square'+'rigged'='SQUARE-RIGGED'

I've seen this clue in The Guardian.

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