Surprisingly lean actor, not a great improviser (8)

I believe the answer is:

coltrane

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'great improviser' is the definition.
The definition suggests a singular noun which matches the answer.

'surprisingly lean actor not a' is the wordplay.
'surprisingly' indicates anagramming the letters (a surprising ordering of the letters).
'not' suggests deleting specific letters.
'lean'+'actor'='leanactor'
'leanactor' with 'a' taken away is 'lenactor'.
'lenactor' is an anagram of 'COLTRANE'.

Can you help me to learn more?

(Another definition for coltrane that I've seen is " saxophonist".)

I've seen this clue in The Independent.

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