Crudeness of crazy, impressive nit! (13)

I believe the answer is:

primitiveness

'crudeness' is the definition.
('primitiveness' can be a synonym of 'crudeness')

'crazy impressive nit' is the wordplay.
'crazy' indicates anagramming the letters.
'impressive'+'nit'='impressivenit'
'impressivenit' anagrammed gives 'PRIMITIVENESS'.

'of' acts as a link.

I've seen this clue in The Telegraph.

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