Son flusters about causing tension (9)

I believe the answer is:

stressful

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'causing tension' is the definition.
I can't tell whether this defines the answer.

'son flusters about' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'about' indicates an anagram.
'flusters' is an anagram of 'tressful'.
's'+'tressful'='STRESSFUL'

Can you help me to learn more?

(Other definitions for stressful that I've seen before include "tense" , "Very hard on the nerves" , "Worrying" , "under great pressure" , "Causing mental tension" .)

I've seen this clue in The Independent.

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