Wan desultory ambition stirred, receiving a comment on extended construction times (4,3,3,5,2,1,3)

I believe the answer is:

rome was not built in a day

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'wan desultory ambition stirred receiving a comment on extended construction times' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'wan desultory ambition stirred receiving a' is the wordplay.
'stirred' indicates anagramming the letters.
'receiving' is an insertion indicator.
'wan'+'desultory'+'ambition'='wandesultoryambition'
'wandesultoryambition' with letters rearranged gives 'romewsnotbuiltinaday'.
'romewsnotbuiltinaday' going around 'a' is 'ROME WAS NOT BUILT IN A DAY'.

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I've seen this clue in The Times.

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