Rabbi led astray by one unprepared for speech (2-6)

I believe the answer is:

ad-libber

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'rabbi led astray by one unprepared for speech' is the definition.
I can't judge whether this definition defines the answer.

'rabbi led astray' is the wordplay.
'astray' is an anagram indicator.
'rabbi'+'led'='rabbiled'
'rabbiled' anagrammed gives 'AD-LIBBER'.

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I've seen this clue in The Guardian.

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