Without doubt one French pursuit decreasing right away (13)

I believe the answer is:

unquestioning

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'without doubt one french pursuit decreasing right away' is the definition.
I can't tell whether this definition defines the answer.

'one french pursuit decreasing right away' is the wordplay.
'one french' becomes 'un' ('one' in French).
'pursuit' becomes 'quest' (synonyms).
'decreasing' becomes 'ironing' (de-creasing: removing creases).
'right' becomes 'r' (common abbreviation).
'away' indicates named letters should be taken away.
'ironing' with 'r' taken away is 'ioning'.
'un'+'quest'+'ioning'='UNQUESTIONING'

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(Another definition for unquestioning that I've seen is " Not expressing doubt".)

I've seen this clue in The Telegraph.

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