Mess one clears up if only slight (11)

I believe the answer is:

superficial

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'only slight' is the definition.
'superficial' can be an answer for 'slight' (similar in meaning). I am not certain of the 'only' bit.

'mess one clears up if' is the wordplay.
'mess' is an anagram indicator.
'one' becomes 'i' (Roman numeral).
'i'+'clears'+'up'+'if'='iclearsupif'
'iclearsupif' anagrammed gives 'SUPERFICIAL'.

Can you help me to learn more?

(Other definitions for superficial that I've seen before include "Not profound" , "Cursory" , "12 [TWO DIMENSIONAL]" , "Far from thorough" .)

I've seen this clue in The Times.

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