Showing off inner grace with shop manager? (6,2,6)

I believe the answer is:

person in charge

'showing off' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'inner grace with shop manager?' is the wordplay.
'with' is a charade indicator (letters next to each other).
'manager?' indicates an anagram (I've seen 'manager' mean this).
'inner'+'grace'+'shop'='innergraceshop'
'innergraceshop' with letters rearranged gives 'PERSON IN CHARGE'.

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

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