Take into context Robert Hughe's 'nothing if not'. 'nothing if not' doesn't contain a prepositional phrase until you add something at the end (i.e. nothing if not something) My phrase contains a fixed prepositional phrase, meaning that it shouldn't be altered, lest the phrase is changed entirely.
'Nothing off of it' as in 'I may have aqcuired nothing off of it', denoting the notion the phrase should be used later in a conversation when 'it' has already been established. I make no claim to own part of the english language, nor does Robert Hughes, however I come to present this part to you as a finding from my studies.
If you can use this phrase 'nothing off of it' then go ahead and use it, it is definitely english language.
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