Drunks are so smooth? (4,5)

I believe the answer is:

well-oiled

'drunks are' is the definition.
(well-oiled can mean drunk)

'so smooth?' is the wordplay.
'so' becomes 'well' (I've seen this before).
'smooth?' becomes 'oiled'.
'well'+'oiled'='WELL-OILED'

(Other definitions for well-oiled that I've seen before include "Drunk (as a smoothly working hinge?)" , "Thoroughly lubricated, or quite drunk" , "Drunk - without squeaks?" .)

I've seen this clue in The Times.

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