24 May Ladner's original diagonalization technique for generating NP-intermediate problems, blowing holes, has a serious shortcoming: it creates. We consider methods for constructing NP-intermediate problems under the assumption that P ≠ NP. We generalize Ladner's original method for obtaining. Definition of blow a hole in in the Idioms Dictionary. blow a hole in phrase. What does blow a hole in expression mean? Definitions by the largest Idiom.