Crossword Genius

Two numbers by vacuous entertainers may be non-starters (2,4)

Ross

I believe the answer is:

no-noes

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'be non-starters' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'two numbers by vacuous entertainers' is the wordplay.
'two numbers' can mean two replacements for 'number'.
'number' becomes 'no' (abbreviation for 'number').
'number' becomes 'no' (abbreviation for 'number').
'by' is a charade indicator (letters next to each other).
'vacuous' suggests removing the centre.
'entertainers' with its centre taken out is 'es'.
'no'+'no'+'es'='NO-NOES'

'may' acts as a link.

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I've seen this clue in The Telegraph.
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