A cleft sentence has a corresponding non-cleft sentence, as in:

It was Tom that invented this. [cleft]

Tom invented this. [non-cleft]

A Comprehensive Grammar of the English Language (Quirk et al.) presents this cleft sentence where the personal pronoun he is the subject instead of it:

(1) He was a real genius that invented this. [cleft?]

In the intended reading, a real genius that invented this does not form a noun phrase. Assuming this, is (1) really a cleft sentence? If it is, what’s the corresponding non-cleft?

Note that he is being used referentially.