Leyton, not having Circle Line, developed in moderate fashion (9)

I believe the answer is:

leniently

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'leyton not having circle line developed in moderate fashion' is the definition.
I can't tell whether this definition defines the answer.

'leyton not having circle line developed' is the wordplay.
'not having' is a deletion indicator.
'circle' becomes 'O' (O is a circle).
'developed' is an anagram indicator.
'leyton' with 'o' taken away is 'leytn'.
'leytn'+'line'='leytnline'
'leytnline' is an anagram of 'LENIENTLY'.

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(Other definitions for leniently that I've seen before include "In a merciful manner" , "Mercifully" .)

I've seen this clue in The Independent.

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